Are animal models relevant to key aspects of human parturition?

American Journal of Physiology - Regulatory Integrative and Comparative Physiology

Volumn 297, Issue 3, 2009, Pages

  Mitchell, Bryan F ^a   Taggart, Michael J ^b  

^a UNIVERSITY OF ALBERTA   (Canada)

^b NEWCASTLE UNIVERSITY   (United Kingdom)

Author keywords

Cervical ripening; Modular accumulation of physiological systems; Progesterone withdrawal; Uterine activation

Indexed keywords

PROGESTERONE;

ANIMAL USE; BIOLOGICAL MODEL; BIRTH; CHILD DEATH; GUINEA PIG; HORMONAL REGULATION; HUMAN; IMMUNE SYSTEM; INFLAMMATION; INTRAUTERINE INFECTION; LUTEOLYSIS; NONHUMAN; PREGNANCY; PREGNANCY COMPLICATION; PREMATURE LABOR; PRIORITY JOURNAL; REGULATORY MECHANISM; REVIEW; SPECIES COMPARISON; UTERUS CONTRACTION;

ANIMALS; CERVICAL RIPENING; FEMALE; GESTATIONAL AGE; GUINEA PIGS; HUMANS; IMMUNE SYSTEM; MICE; MODELS, ANIMAL; MYOMETRIUM; PARTURITION; PREGNANCY; PROGESTERONE; RABBITS; RATS; SHEEP; SIGNAL TRANSDUCTION; SPECIES SPECIFICITY; UTERINE CONTRACTION;

EID: 69249125384     PISSN: 03636119     EISSN: 15221490     Source Type: Journal    
DOI: 10.1152/ajpregu.00153.2009     Document Type: Review

References (232)

1. Adams Waldorf KM, Persing D, Novy MJ, Sadowsky DW, Gravett MG. Pretreatment with toll-like receptor 4 antagonist inhibits lipopolysaccharide- induced preterm uterine contractility, cytokines, and prostaglandins in rhesus monkeys. Reprod Sci 15: 121-127, 2008.
2. Alexandrova M, Soloff MS. Oxytocin receptors and parturition in the guinea pig. Biol Reprod 22: 1106-1111, 1980.
3. Althabe F, Belizan JM. Caesarean section: the paradox. Lancet 368: 1472-1473, 2006.
4. Antonijevic IA, Douglas AJ, Dye S, Bicknell RJ, Leng G, Russell JA. Oxytocin antagonists delay the initiation of parturition and prolong its active phase in rats. J Endocrinol 145: 97-103, 1995.
5. Arkinstall SJ, Jones CT. Influence of pregnancy on G-protein coupling to adenylate cyclase activation in guinea-pig myometrium. J Endocrinol 127: 15-21, 1990.
6. Arkinstall SJ, Jones CT. Pregnancy suppresses G protein coupling to phosphoinositide hydrolysis in guinea pig myometrium. Am J Physiol Endocrinol Metab 259: E57-E65, 1990.
7. Arthur P, Taggart MJ, Mitchell BF. Oxytocin and parturition: a role for increased myometrial calcium and calcium sensitization? Front Biosci 12: 619-633, 2007.
8. Arthur P, Taggart MJ, Zielnik B, Wong S, Mitchell BF. Relationships between gene expression and function of uterotonic systems in the rat during gestation, uterine activation and both term and preterm labour. J Physiol 586: 6063-6076, 2008.
9. Attardi BJ, Zeleznik A, Simhan H, Chiao JP, Mattison DR, Caritis SN. Comparison of progesterone and glucocorticoid receptor binding and stimulation of gene expression by progesterone, 17-alpha hydroxyprogesterone caproate, and related progestins. Am J Obstet Gynecol 197: 599.e1-599.e7, 2007.
10. Aubeny E. RU486 combined with PG analogs in voluntary termination of pregnancy. Adv Contracept 7: 339-343, 1991.
11. Baggia S, Gravett MG, Witkin SS, Haluska GJ, Novy MJ. Interleukin-1 beta intra-amniotic infusion induces tumor necrosis factor-alpha, prostaglandin production, and preterm contractions in pregnant rhesus monkeys. J Soc Gynecol Investig 3: 121-126, 1996.
12. Bansal RK, Goldsmith PC, He Y, Zaloudek CJ, Ecker JL, Riemer RK. A decline in myometrial nitric oxide synthase expression is associated with labor and delivery. J Clin Invest 99: 2502-2508, 1997.
13. Bartholomeusz RK, Bruce NW, Martin CE, Hartmann PE. Serial measurement of arterial plasma progesterone levels throughout gestation and parturition in individual rats. Acta Endocrinol (Copenh) 82: 436-443, 1976.
14. Bartlett NR, Hobkirk R. Estrogen sulfotransferase and 17 beta-hydroxysteroid dehydrogenase activities in guinea-pig chorion through gestation. J Steroid Biochem Mol Biol 38: 241-247, 1991.
15. Bassett JM, Oxborrow TJ, Smith ID, Thorburn GD. The concentration of progesterone in the peripheral plasma of the pregnant ewe. J Endocrinol 45: 449-457, 1969.
16. Behrman RE, Butler AS. Preterm Birth: Causes, Consequences, Prevention. Washington: National Academies, 2007.
17. Bernal AL, Flint AP, Anderson AB, Turnbull AC. 11β-Hydroxysteroid dehydrogenase activity (E.C. 111146) in human placenta and decidua. J Steroid Biochem 13: 1081-1087, 1980.
18. Boroditsky RS, Reyes FI, Winter JS, Faiman C. Maternal serum estrogen and progesterone concentrations preceding normal labor. Obstet Gynecol 51: 686-691, 1978.
19. Breuiller-Fouche M, Charpigny G, Germain G. Functional genomics of the pregnant uterus: from expectations to reality, a compilation of studies in the myometrium. BMC Pregnancy Childbirth 7, Suppl 1: S4, 2007.
20. Brodt-Eppley J, Myatt L. Prostaglandin receptors in lower segment myometrium during gestation and labor. Obstet Gynecol 93: 89-93, 1999.
21. + channels depresses phasic uterine contraction. Am J Physiol Cell Physiol 292: C832-C840, 2007.
22. Brownfoot FC, Crowther CA, Middleton P. Different corticosteroids and regimens for accelerating fetal lung maturation for women at risk of preterm birth. Cochrane Database Syst Rev: CD006764, 2008.
23. Bugg GJ, Stanley E, Baker PN, Taggart MJ, Johnston TA. Outcomes of labors augmented with oxytocin. Eur J Obstet Gynecol Reprod Biol 124: 37-41, 2006.
24. Buhimschi IA, Dussably L, Buhimschi CS, Ahmed A, Weiner CP. Physical and biomechanical characteristics of rat cervical ripening are not consistent with increased collagenase activity. Am J Obstet Gynecol 191: 1695-1704, 2004.
25. Bukowski R, Scholz P, Hasan SH, Chwalisz K. Induction of preterm parturition with the interleukin 1b, tumor necrosis factor-a and with LPS in guinea pigs. J Soc Gynecol Invest: S26, 1993.
26. Bulbring E, Casteels R, Kuriyama H. Membrane potential and ion content in cat and guinea-pig myometrium and the response to adrenaline and noradrenaline. Br J Pharmacol 34: 388-407, 1968.
27. Buxton IL. Regulation of uterine function: a biochemical conundrum in the regulation of smooth muscle relaxation. Mol Pharmacol 65: 1051-1059, 2004.
28. Bytautiene E, Vedernikov YP, Saade GR, Romero R, Garfield RE. IgE-independent mast cell activation augments contractility of nonpregnant and pregnant guinea pig myometrium. Int Arch Allergy Immunol 147: 140-146, 2008.
29. Calder AA, Embrey MP, Tait T. Ripening of the cervix with extra-amniotic prostaglandin E2 in viscous gel before induction of labor. Br J Obstet Gynaecol 84: 264-268, 1977.
30. Cameron IT, Bacon CR, Collett GP, Davenport AP. Endothelin expression in the uterus. J Steroid Biochem Mol Biol 53: 209-214, 1995.
31. Carter AM. Animal models of human placentation-a review. Placenta 28, Suppl A: S41-S47, 2007.
32. Challis JR, Mathews SG, Gibb W, Lye SJ. Endocrine and paracrine regulation of birth at term and preterm. Endocr Rev 21: 514-550, 2000.
33. Challis JR, Davies J, Ryan KJ. The concentrations of progesterone, estrone and estradiol-17 beta in the plasma of pregnant rabbits. Endocrinology 93: 971-976, 1973.
34. Challis JRG. Sharp increase in free circulating oestrogens immediately before parturition in sheep. Nature 229: 208, 1971.
35. Challis JRG, Lye SJ. Parturition. In: The Physiology of Reproduction, edited by Knobil E and Neill JD. New York: Raven, 1994, p. 985-1031.
36. Chambers PL, Hearn JP. Peripheral plasma levels of progesterone, oestradiol-17 beta, oestrone, testosterone, androstenedione and chorionic gonadotrophin during pregnancy in the marmoset monkey, Callithrix jacchus. J Reprod Fertil 56: 23-32, 1979.
37. Chandiramani M, Tribe R, Shennan A. Progesterone and preterm birth. N Engl J Med 357: 2306-2307, 2007.
38. Chapman NR, Kennelly MM, Harper KA, Europe-Finner GN, Robson SC. Examining the spatio-temporal expression of mRNA encoding the membrane-bound progesterone receptor-alpha isoform in human cervix and myometrium during pregnancy and labor. Mol Hum Reprod 12: 19-24, 2006.
39. Chibbar R, Hobkirk R, Mitchell BF. Sulfohydrolase activity for estrone sulfate and dehydroepiandrosterone sulfate in human fetal membranes and decidua around the time of parturition. J Clin Endocrinol Metab 62: 90-94, 1986.
40. Chibbar R, Miller FD, Mitchell BF. Synthesis of oxytocin in amnion, chorion, and decidua may influence the timing of human parturition. J Clin Invest 91: 185-192, 1993.
41. Chibbar R, Wong S, Miller FD, Mitchell BF. Estrogen stimulates oxytocin gene expression in human chorio-decidua. J Clin Endocrinol Metab 80: 567-572, 1995.
42. Christian MS, Brent RL, Calda P. Embryo-fetal toxicity signals for 17alpha-hydroxyprogesterone caproate in high-risk pregnancies: a review of the non-clinical literature for embryo-fetal toxicity with progestins. J Matern Fetal Neonatal Med 20: 89-112, 2007.
43. Chwalisz K. The use of progesterone antagonists for cervical ripening and as an adjunct to labor and delivery. Human Reprod 9, Suppl 1: 131-161, 1994.
44. Chwalisz K, Fahrenholz F, Hackenberg M, Garfield R, Elger W. The progesterone antagonist onapristone increases the effectiveness of oxytocin to produce delivery without changing the myometrial oxytocin receptor concentrations. Am J Obstet Gynecol 165: 1760-1770, 1991.
45. Chwalisz K, Garfield RE. Antiprogestins in the induction of labor. Ann NY Acad Sci 734: 387-413, 1994.
46. Chwalisz K, Garfield RE. Regulation of the uterus and cervix during pregnancy and labor. Role of progesterone and nitric oxide. Ann NY Acad Sci 828: 238-253, 1997.
47. Chwalisz K, Garfield RE. Role of progesterone during pregnancy: models of parturition and preeclampsia. Z Geburtshilfe Perinatol 198: 170-180, 1994.
48. Coleman HA, McShane PG, Parkington HC. Gestational changes in the utilization of intracellularly stored calcium in the myometrium of guinea-pigs. J Physiol 399: 13-32, 1988.
49. Collins PL, Moore JJ, Lundgren DW, Choobineh E, Chang SM, Chang AS. Gestational changes in uterine L-type calcium channel function and expression in guinea pig. Biol Reprod 63: 1262-1270, 2000.
50. Condon JC, Jeyasuria P, Faust JM, Wilson JW, Mendelson CR. A decline in the levels of progesterone receptor coactivators in the pregnant uterus at term may antagonize progesterone receptor function and contribute to the initiation of parturition. Proc Natl Acad Sci USA 100: 9518-9523, 2003.
51. Crane JM, Hutchens D. Transvaginal sonographic measurement of cervical length to predict preterm birth in asymptomatic women at increased risk: a systematic review. Ultrasound Obstet Gynecol 31: 579-587, 2008.
52. Csapo AI. Progesterone "block". Am J Anat 98: 273-291, 1956.
53. Csapo AI, Pulkkinen M. Indispensability of the human corpus luteum in the maintenance of early pregnancy. Luteectomy evidence. Obstet Gynecol Surv 33: 69-81, 1978.
54. Csapo AI, Pulkkinen MO, Wiest WG. Effects of luteectomy and progesterone replacement therapy in early pregnant patients. Am J Obstet Gynecol 115: 759-765, 1973.
55. Csapo AI, Puri CP, Tarro S. Relationship between timing of ovariectomy and maintenance of pregnancy in the guinea-pig. Prostaglandins 22: 131-140, 1981.
56. Csapo AI, Wiest WG. An examination of the quantitative relationship between progesterone and the maintenance of pregnancy. Endocrinology 85: 745-746, 1969.
57. Da Fonseca EB, Bittar RE, Carvalho MH, Zugaib M. Prophylactic administration of progesterone by vaginal suppository to reduce the incidence of spontaneous preterm birth in women at increased risk: a randomized placebo-controlled double-blind study. Am J Obstet Gynecol 188: 419-424, 2003.
58. Danforth DN, Buckingham JC, Roddick JW Jr. Connective tissue changes incident to cervical effacement. Am J Obstet Gynecol 80: 939-945, 1960.
59. DeFranco EA, O'Brien JM, Adair CD, Lewis DF, Hall DR, Fusey S, Soma-Pillay P, Porter K, How H, Schakis R, Eller D, Trivedi Y, Vanburen G, Khandelwal M, Trofatter K, Vidyadhari D, Vijayaraghavan J, Weeks J, Dattel B, Newton E, Chazotte C, Valenzuela G, Calda P, Bsharat M, Creasy GW. Vaginal progesterone is associated with a decrease in risk for early preterm birth and improved neonatal outcome in women with a short cervix: a secondary analysis from a randomized, double-blind, placebo-controlled trial. Ultrasound Obstet Gynecol 30: 697-705, 2007.
60. Demirkoprulu N, Cetin M, Bagcivan I, Kaya T, Soydan AS, Karadas B, Cetin A. Comparative relaxant effects of YC-1 and DETA/NO on spontaneous contractions and the levels of cGMP of isolated pregnant rat myometrium. Eur J Pharmacol 517: 240-245, 2005.
61. Denison FC, Calder AA, Kelly RW. The action of prostaglandin E2 on the human cervix: stimulation of interleukin 8 and inhibition of secretory leukocyte protease inhibitor. Am J Obstet Gynecol 180: 614-620, 1999.
62. Doheny HC, Lynch CM, Smith TJ, Morrison JJ. Functional coupling of beta3-adrenoceptors and large conductance calcium-activated potassium channels in human uterine myocytes. J Clin Endocrinol Metab 90: 5786-5796, 2005.
63. Doring B, Shynlova O, Tsui P, Eckardt D, Janssen-Bienhold U, Hofmann F, Feil S, Feil R, Lye SJ, Willecke K. Ablation of connexin43 in uterine smooth muscle cells of the mouse causes delayed parturition. J Cell Sci 119: 1715-1722, 2006.
64. Fang X, Wong S, Mitchell BF. Effects of LPS and IL-6 on oxytocin receptor in non-pregnant and pregnant rat uterus. Am J Reprod Immunol 44: 65-72, 2000.
65. Fang X, Wong S, Mitchell BF. Effects of RU486 on estrogen, progesterone, oxytocin, and their receptors in the rat uterus during late gestation. Endocrinology 138: 2763-2768, 1997.
66. Fang X, Wong S, Mitchell BF. Messenger RNA for progesterone receptor isoforms in the late-gestation rat uterus. Am J Physiol Endocrinol Metab 283: E1167-E1172, 2002.
67. Fang X, Wong S, Mitchell BF. Relationships among sex steroids, oxytocin, and their receptors in the rat uterus during late gestation and at parturition. Endocrinology 137: 3213-3219, 1996.
68. Fernandez-Patron C, Stewart KG, Zhang Y, Koivunen E, Radomski MW, Davidge ST. Vascular matrix metalloproteinase-2-dependent cleavage of calcitonin gene-related peptide promotes vasoconstriction. Circ Res 87: 670-676, 2000.
69. Fetalvero KM, Zhang P, Shyu M, Young BT, Hwa J, Young RC, Martin KA. Prostacyclin primes pregnant human myometrium for an enhanced contractile response in parturition. J Clin Invest 118: 3966-3979, 2008.
70. Fidel PL Jr, Romero R, Wolf N, Cutright J, Ramirez M, Araneda H, Cotton DB. Systemic and local cytokine profiles in endotoxin-induced preterm parturition in mice. Am J Obstet Gynecol 170: 1467-1475, 1994.
71. Filipovich Y, Lu SJ, Akira S, Hirsch E. The adaptor protein MyD88 is essential for E. coli-induced preterm delivery in mice. Am J Obstet Gynecol 200: 93 e91-e98, 2009.
72. Fonseca EB, Celik E, Parra M, Singh M, Nicolaides KH. Progesterone and the risk of preterm birth among women with a short cervix. N Engl J Med 357: 462-469, 2007.
73. Fortson W, Beharry KD, Nageotte S, Sills JH, Stavitsky Y, Asrat T, Modanlou HD. Vaginal versus oral indomethacin in a rabbit model for non-infection-mediated preterm birth: an alternate tocolytic approach. Am J Obstet Gynecol 195: 1058-1064, 2006.
74. Frydman R, Lelaidier C, Baton-Saint-Mleux C, Fernandez H, Vial M, Bourget P. Labor induction in women at term with mifepristone (RU 486): a double-blind, randomized, placebo-controlled study. Obstet Gynecol 80: 972-975, 1992.
75. Fuchs AR. Hormonal control of myometrial function during pregnancy and parturition. Acta Endocrinol Suppl (Copenh) 221: 1-70, 1978.
76. Fuchs AR, Fuchs F, Husslein P, Soloff MS, Fernstrom MJ. Oxytocin receptors and human parturition: a dual role for oxytocin in the initiation of labor. Science 215: 1396-1398, 1982.
77. Garfield RE, Daniel EE, Dukes M, Fitzgerald JD. Changes of gap junctions in myometrium of guinea pig at parturition and abortion. Can J Physiol Pharmacol 60: 335-341, 1982.
78. Garfield RE, Kannan MS, Daniel EE. Gap junction formation in myometrium: control by estrogens, progesterone, and prostaglandins. Am J Physiol Cell Physiol 238: C81-C89, 1980.
79. Germain G, Cabrol C, Visser A, Sultan C. Electrical activity of the pregnant uterus of the cynomolgus monkey. Am J Obstet Gynecol 142: 448-457, 1982.
80. Gibb W, Lavoie JC. Steroid aromatization by term human fetal membranes. J Steroid Biochem 14: 401-403, 1981.
81. Gibb W, Lavoie JC, Roux J. In vitro conversion of pregnenolone to progesterone by term human fetal membranes. Am J Obstet Gynecol 136: 631-634, 1980.
82. Glasier MA, Wiebe JP, Hobkirk R. Progesterone metabolism by guinea pig intrauterine tissues. J Steroid Biochem Mol Biol 51: 199-207, 1994.
83. Glutek SM, Hobkirk R. Estrogen sulfatase and steroid sulfatase activities in intrauterine tissues of the pregnant guinea pig. J Steroid Biochem Mol Biol 37: 707-715, 1990.
84. Golander A, Hurley T, Barrett J, Handwerger S. Synthesis of prolactin by human decidua in vitro. J Endocrinol 82: 263-267, 1979.
85. Goldenberg RL, Culhane JF, Iams JD, Romero R. Epidemiology and causes of preterm birth. Lancet 371: 75-84, 2008.
86. Goldenberg RL, Hauth JC, Andrews WW. Intrauterine infection and preterm delivery. N Engl J Med 342: 1500-1507, 2000.
87. Goshowaki H, Ito A, Mori Y. Effects of prostaglandins on the production of collagenase by rabbit uterine cervical fibroblasts. Prostaglandins 36: 107-114, 1988.
88. Goy RW, Hoar RM, Young WC. Length of gestation in the guinea pig with data on the frequency and time of abortion and stillbirth. Anat Rec 128: 747-757, 1957.
89. Granstrom L, Ekman G, Ulmsten U, Malmstrom A. Changes in the connective tissue of corpus and cervix uteri during ripening and labor in term pregnancy. Br J Obstet Gynaecol 96: 1198-1202, 1989.
90. Gravett MG, Witkin SS, Haluska GJ, Edwards JL, Cook MJ, Novy MJ. An experimental model for intraamniotic infection and preterm labor in rhesus monkeys. Am J Obstet Gynecol 171: 1660-1667, 1994.
91. Grazzini E, Guillon G, Mouillac B, Zingg HH. Inhibition of oxytocin receptor function by direct binding of progesterone. Nature 392: 509-512, 1998.
92. Green NS, Damus K, Simpson JL, Iams J, Reece EA, Hobel CJ, Merkatz IR, Greene MF, Schwarz RH. Research agenda for preterm birth: recommendations from the March of Dimes. Am J Obstet Gynecol 193: 626-635, 2005.
93. Grigsby PL, Sooranna SR, Adu-Amankwa B, Pitzer B, Brockman DE, Johnson MR, Myatt L. Regional expression of prostaglandin E2 and F2alpha receptors in human myometrium, amnion, and choriodecidua with advancing gestation and labor. Biol Reprod 75: 297-305, 2006.
94. Gross GA, Imamura T, Luedke C, Vogt SK, Olson LM, Nelson DM, Sadovsky Y, Muglia LJ. Opposing actions of prostaglandins and oxytocin determine the onset of murine labor. Proc Natl Acad Sci USA 95: 11875-11879, 1998.
95. Gyetvai K, Hannah ME, Hodnett ED, Ohlsson A. Tocolytics for preterm labor: a systematic review. Obstet Gynecol 94: 869-877, 1999.
96. Hasegawa A, Otsuki K, Sasaki Y, Sawada M, Mitsukawa K, Chiba H, Nagatsuka M, Okai T, Kato A. Preventive effect of recombinant human lactoferrin in a rabbit preterm delivery model. Am J Obstet Gynecol 192: 1038-1043, 2005.
97. Havelock JC, Keller P, Muleba N, Mayhew BA, Casey BM, Rainey WE, Word RA. Human myometrial gene expression before and during parturition. Biol Reprod 72: 707-719, 2005.
98. Health Canada. Canadian Perinatal Health Report, 2000. Ottawa, ON: Minister of Public Works and Government Services Canada, 2000.
99. Heap RB, Deanesly R. Progesterone in systemic blood and placentae of intact and ovariectomized pregnant guinea-pigs. J Endocrinol 34: 417-423, 1966.
100. Helmer H, Tretzmuller U, Brunbauer M, Kaider A, Husslein P, Knofler M. Production of oxytocin receptor and cytokines in primary uterine smooth muscle cells cultivated under inflammatory conditions. J Soc Gynecol Investig 9: 15-21, 2002.
101. Hendrickx AG, Korte R, Leuschner F, Neumann BW, Poggel A, Binkerd P, Prahalada S, Gunzel P. Embryotoxicity of sex steroidal hormones in nonhuman primates: II. Hydroxyprogesterone caproate, estradiol valerate. Teratology 35: 129-136, 1987.
102. Hirsch E, Filipovich Y, Romero R. Failure of E. coli bacteria to induce preterm delivery in the rat. J Negat Results Biomed 8: 1, 2009.
103. Hirsch E, Muhle RA, Mussalli GM, Blanchard R. Bacterially induced preterm labor in the mouse does not require maternal interleukin-1 signaling. Am J Obstet Gynecol 186: 523-530, 2002.
104. Hobkirk R, Glasier MA. Generation of estradiol within the pregnant guinea pig uterine compartment with special reference to the myometrium. J Steroid Biochem Mol Biol 44: 291-297, 1993.
105. Horwitz KB, Alexander PS. In situ photolinked nuclear progesterone receptors of human breast cancer cells: subunit molecular weights after transformation and translocation. Endocrinology 113: 2195-2201, 1983.
106. Hovland AR, Powell RL, Takimoto GS, Tung L, Horwitz KB. An N-terminal inhibitory function, IF, suppresses transcription by the A-isoform but not the B-isoform of human progesterone. J Biol Chem 10: 5455-5460, 1998.
107. Hutzal CE, Boyle EM, Kenyon SL, Nash JV, Winsor S, Taylor DJ, Kirpalani H. Use of antibiotics for the treatment of preterm parturition and prevention of neonatal morbidity: a metaanalysis. Am J Obstet Gynecol 199: 620.e1-620.e8, 2008.
108. Imamura T, Luedke CE, Vogt SK, Muglia LJ. Oxytocin modulates the onset of murine parturition by competing ovarian and uterine effects. Am J Physiol Regul Integr Comp Physiol 279: R1061-R1067, 2000.
109. Johnson JW, Austin KL, Jones GS, Davis GH, King TM. Efficacy of 17alpha-hydroxyprogesterone caproate in the prevention of premature labor. N Engl J Med 293: 675-680, 1975.
110. Junqueira LC, Zugaib M, Montes GS, Toledo OM, Krisztan RM, Shigihara KM. Morphologic and histochemical evidence for the occurrence of collagenolysis and for the role of neutrophilic polymorphonuclear leukocytes during cervical dilation. Am J Obstet Gynecol 138: 273-281, 1980.
111. Kalkhoven E, Wissink S, van der Saag PT, van der Burg B. Negative interaction between the RelA(p65) subunit of NF-kappaB and the progesterone receptor. J Biol Chem 271: 6217-6224, 1996.
112. Karsdon J, Garfield RE, Shi SQ, Maner W, Saade G. Electrical inhibition of preterm birth: inhibition of uterine contractility in the rabbit and pup births in the rat. Am J Obstet Gynecol 193: 1986-1993, 2005.
113. Karteris E, Zervou S, Pang Y, Dong J, Hillhouse EW, Randeva HS, Thomas P. Progesterone signaling in human myometrium through two novel membrane G protein-coupled receptors: potential role in functional progesterone withdrawal at term. Mol Endocrinol 20: 1519-1534, 2006.
114. Keelan JA, Blumenstein M, Helliwell RJ, Sato TA, Marvin KW, Mitchell MD. Cytokines, prostaglandins and parturition - a review. Placenta 24, Suppl A: S33-S46, 2003.
115. Kelly RW. Inflammatory mediators and cervical ripening. J Reprod Immunol 57: 217-224, 2002.
116. Kemp B, Winkler M, Maas A, Maul H, Ruck P, Reineke T, Rath W. Cytokine concentrations in the amniotic fluid during parturition at term: correlation to lower uterine segment values and to labor. Acta Obstet Gynecol Scand 81: 938-942, 2002.
117. Kenyon SL, Taylor DJ, Tarnow-Mordi W. Broad-spectrum antibiotics for preterm, prelabor rupture of fetal membranes: the ORACLE I randomised trial. ORACLE Collaborative Group. Lancet 357: 979-988, 2001.
118. Kenyon SL, Taylor DJ, Tarnow-Mordi W. Broad-spectrum antibiotics for spontaneous preterm labor: the ORACLE II randomised trial. ORACLE Collaborative Group. Lancet 357: 989-994, 2001.
119. Kitamura K, Ito A, Mori Y, Hirakawa S. Glycosaminoglycans of human uterine cervix: heparan sulfate increase with reference to cervical ripening. Biochem Med 23: 159-166, 1980.
120. Kupittayanant S, Burdyga T, Wray S. The effects of inhibiting Rho-associated kinase with Y-27632 on force and intracellular calcium in human myometrium. Pflügers Arch 443: 112-114, 2001.
121. Lammers WJ, Mirghani H, Stephen B, Dhanasekaran S, Wahab A, Al Sultan MA, Abazer F. Patterns of electrical propagation in the intact pregnant guinea pig uterus. Am J Physiol Regul Integr Comp Physiol 294: R919-R928, 2008.
122. Lamont RF. Antibiotics used in women at risk of preterm birth. Am J Obstet Gynecol 199: 583-584, 2008.
123. Lee YH, Hwang MK, Morgan KG, Taggart MJ. Receptor-coupled contractility of uterine smooth muscle: from membrane to myofilaments. Exp Physiol 86: 283-288, 2001.
124. Leppert PC. Anatomy and physiology of cervical ripening. Clin Obstet Gynecol 38: 267-279, 1995.
125. Liggins GC. Cervical ripening as an inflammatory reaction. In: The Cervix in Pregnancy and Labor, Clinical and Biochemical Investigations, edited by Elwood DA, Anderson, AB. Edinburgh: Churchill Livingstone, 1981, p. 1-9.
126. Luckas MJ, Wray S. A comparison of the contractile properties of human myometrium obtained from the upper and lower uterine segments. BJOG 107: 1309-1311, 2000.
127. Madsen G, Macintyre DA, Mesiano S, Smith R. Progesterone receptor or cytoskeletal protein? Reprod Sci 14: 217-222, 2007.
128. Mahendroo MS, Cala KM, Russell DW. 5 alpha-reduced androgens play a key role in murine parturition. Mol Endocrinol 10: 380-392, 1996.
129. Mahendroo MS, Porter A, Russell DW, Word RA. The parturition defect in steroid 5alpha-reductase type 1 knockout mice is due to impaired cervical ripening. Mol Endocrinol 13: 981-992, 1999.
130. Mangham LJ, Petrou S, Doyle LW, Draper ES, Marlow N.The cost of preterm birth throughout childhood in England and Wales. Pediatrics 123: e312-e327, 2009.
131. Manjeli Y, Tchoumboue J, Njwe RM, Teguia A. Guinea-pig productivity under traditional management. Trop Anim Health Prod 30: 115-122, 1998.
132. Manning JP, Wagner JE, Harkness JE. Biology and diseases of guinea pigs. In: Laboratory Animal Medicine, edited by Fox JG, Cohen BJ, and Loew FM. New York: Academic, 1984, p. 91-122.
133. Marc S, Leiber D, Harbon S. Carbachol and oxytocin stimulate the generation of inositol phosphates in the guinea pig myometrium. FEBS Lett 201: 9-14, 1986.
134. Marx SG, Wentz MJ, Mackay LB, Schlembach D, Maul H, Fittkow C, Given R, Vedernikov Y, Saade GR, Garfield RE. Effects of progesterone on iNOS, COX-2, and collagen expression in the cervix. J Histochem Cytochem 54: 623-639, 2006.
135. Mason CW, Swaan PW, Weiner CP. Identification of interactive gene networks: a novel approach in gene array profiling of myometrial events during guinea pig pregnancy. Am J Obstet Gynecol 194: 1513-1523, 2006.
136. Maul H, Mackay L, Garfield RE. Cervical ripening: biochemical, molecular, and clinical considerations. Clin Obstet Gynecol 49: 551-563, 2006.
137. Meis PJ. 17 Hydroxyprogesterone for the prevention of preterm delivery. Obstet Gynecol 105: 1128-1135, 2005.
138. Mendelson CR. Minireview: fetal-maternal hormonal signaling in pregnancy and labor. Mol Endocrinol 23: 947-954, 2009.
139. Merlino AA, Welsh TN, Tan H, Yi LJ, Cannon V, Mercer BM, Mesiano S. Nuclear progesterone receptors in the human pregnancy myometrium: evidence that parturition involves functional progesterone withdrawal mediated by increased expression of progesterone receptor-A. J Clin Endocrinol Metab 92: 1927-1933, 2007.
140. Mesiano S, Chan EC, Fitter JT, Kwek K, Yeo G, Smith R. Progesterone withdrawal and estrogen activation in human parturition are coordinated by progesterone receptor A expression in the myometrium. J Clin Endocrinol Metab 87: 2924-2930, 2002.
141. Mitchell BF, Challis JR, Lukash L. Progesterone synthesis by human amnion, chorion, and decidua at term. Am J Obstet Gynecol 157: 349-353, 1987.
142. Mitchell BF, Challis JRG. Estrogen and progesterone metabolism in human fetal membranes. In: The Physiology and Biochemistry of Human Fetal Membranes, edited by Mitchell BF. Ithaca, NY: Perinatology, 1988, p. 5-28.
143. Mitchell BF, Cross J, Hobkirk R, Challis JR. Formation of unconjugated estrogens from estrone sulfate by dispersed cells from human fetal membranes and decidua. J Clin Endocrinol Metab 58: 845-849, 1984.
144. Mitchell BF, Mitchell JM, Chowdhury J, Tougas M, Engelen SM, Senff N, Heijnen I, Moore JT, Goodwin B, Wong S, Davidge ST. Metabolites of progesterone and the pregnane X receptor: a novel pathway regulating uterine contractility in pregnancy? Am J Obstet Gynecol 192: 1304-1313, 2005.
145. Mitchell BF, Wong S. Changes in 17 beta,20 alpha-hydroxysteroid dehydrogenase activity supporting an increase in the estrogen/progesterone ratio of human fetal membranes at parturition. Am J Obstet Gynecol 168: 1377-1385, 1993.
146. Mitchell BF, Zielnik B, Wong S, Roberts CD, Mitchell JM. Intraperitoneal infusion of pro-inflammatory cytokines does not cause activation of the rat uterus during late gestation. Am J Physiol Endocrinol Metab 289: E658-E664, 2005.
147. Muglia L, Jacobson L, Dikkes P, Majzoub JA. Corticotropin- releasing hormone deficiency reveals major fetal but not adult glucocorticoid need. Nature 373: 427-432, 1995.
148. Nagao K, Kohno N, Wakita K, Hikiji K, Yamamoto S, Hirata H, Hisatomi H. Expression of a novel splicing variant deleting exons 4 and 6 of the progesterone receptor gene is a rare event in breast cancer. Oncol Rep 10: 305-308, 2003.
149. Nakayama K, Otsuki K, Yakuwa K, Hasegawa A, Sawada M, Mitsukawa K, Chiba H, Nagatsuka M, Okai T. Recombinant human lactoferrin inhibits matrix metalloproteinase (MMP-2, MMP-3, and MMP-9) activity in a rabbit preterm delivery model. J Obstet Gynaecol Res 34: 931-934, 2008.
150. Neilson JP. Mifepristone for induction of labor. Cochrane Database Syst Rev: CD002865, 2000.
151. Nishimori K, Young LJ, Guo Q, Wang Z, Insel TR. Oxytocin is required for nursing but is not essential for parturition or reproductive behavior. Proc Natl Acad Sci USA 93: 11699-11704, 1996.
152. Noble D. The Music of Life. Biology Beyond the Genome. Oxford: Oxford University Press, 2006.
153. Norman JE. Preterm labor. Cervical function and prematurity. Best Pract Res Clin Obstet Gynaecol 21: 791-806, 2007.
154. Norman JE, Bollapragada S, Yuan M, Nelson SM. Inflammatory pathways in the mechanism of parturition. BMC Pregnancy Childbirth 7, Suppl 1: S7, 2007.
155. North D. The guinea-pig. In: The UFAW Handbook on the Care and Management of Laboratory Animals (7th ed.), edited by Poole T. Oxford: Blackwell Science, 1999, p. 367-388.
156. O'Brien JM, Adair CD, Lewis DF, Hall DR, Defranco EA, Fusey S, Soma-Pillay P, Porter K, How H, Schackis R, Eller D, Trivedi Y, Vanburen G, Khandelwal M, Trofatter K, Vidyadhari D, Vijayaraghavan J, Weeks J, Dattel B, Newton E, Chazotte C, Valenzuela G, Calda P, Bsharat M, Creasy GW. Progesterone vaginal gel for the reduction of recurrent preterm birth: primary results from a randomized, double-blind, placebo-controlled trial. Ultrasound Obstet Gynecol 30: 687-696, 2007.
157. Olson DM, Skinner K, Challis JRG. Prostaglandin output in relation to parturition by cells dispersed from human intrauterine tissues. J Clin Endocrinol Metab 57: 694-699, 1983.
158. Olson DM, Zakar T, Mitchell BF. Prostaglandin synthesis regulation by intrauterine tissues. In: Molecular Aspects of Placental and Fetal Membrane Autocoids, edited by Rice GE and Brennecke SP. Boca Raton, FL: CRC, 1993, p. 56-95.
159. Opsjon SL, Wathen NC, Tingulstad S, Wiedswang G, Sundan A, Waage A, Austgulen R. Tumor necrosis factor, interleukin-1, and interleukin-6 in normal human pregnancy. Am J Obstet Gynecol 169: 397-404, 1993.
160. Orsi NM, Tribe RM. Cytokine networks and the regulation of uterine function in pregnancy and parturition. J Neuroendocrinol 20: 462-469, 2008.
161. Osman I, Young A, Ledingham MA, Thomson AJ, Jordan F, Greer IA, Norman JE. Leukocyte density and pro-inflammatory cytokine expression in human fetal membranes, decidua, cervix and myometrium before and during labor at term. Mol Hum Reprod 9: 41-45, 2003.
162. Ozaki H, Yasuda K, Kim YS, Egawa M, Kanzaki H, Nakazawa H, Hori M, Seto M, Karaki H. Possible role of the protein kinase C/CPI-17 pathway in the augmented contraction of human myometrium after gestation. Br J Pharmacol 140: 1303-1312, 2003.
163. Perusquia M, Jasso-Kamel J. Influence of 5alpha- and 5beta-reduced progestins on the contractility of isolated human myometrium at term. Life Sci 68: 2933-2944, 2001.
164. Phaneuf S, Asboth G, Carrasco MP, Linares BR, Kimura T, Harris A, Bernal AL. Desensitization of oxytocin receptors in human myometrium. Hum Reprod Update 4: 625-633, 1998.
165. Pierce SL, Kresowik JD, Lamping KG, England SK. Overexpression of SK3 channels dampens uterine contractility to prevent preterm labor in mice. Biol Reprod 78: 1058-1063, 2008.
166. Porter DG. The failure of progesterone to affect myometrial activity in the guinea-pig. J Endocrinol 46: 425-434, 1970.
167. Porter DG, Challis JR. Failure of high uterine concentrations of progesterone to inhibit myometrial activity in vivo in the post-partum rat. J Reprod Fertil 39: 157-162, 1974.
168. Powell WA, Mitchell BF, Challis JR. Effects of steroids on progesterone output by explants of human chorion. Gynecol Obstet Invest 22: 64-72, 1986.
169. Price SA, Pochun I, Phaneuf S, Lopez Bernal A. Adenylyl cyclase isoforms in pregnant and non-pregnant human myometrium. J Endocrinol 164: 21-30, 2000.
170. Putnam CD, Brann DW, Kolbeck RC, Mahesh VB. Inhibition of uterine contractility by progesterone and progesterone metabolites: mediation by progesterone and gamma amino butyric acidA receptor systems. Biol Reprod 45: 266-272, 1991.
171. Ratajczak CK, Muglia LJ. Insights into parturition biology from genetically altered mice. Pediatr Res 64: 581-589, 2008.
172. Rath W, Osmers R, Stuhlsatz HW, Adelmann-Grill BC. Biochemical principles of cervix ripening and dilatation [in German]. Z Geburtshilfe Perinatol 198: 186-195, 1994.
173. Rauk PN, Chiao JP. Oxytocin signaling in human myometrium is impaired by prolonged exposure to interleukin-1. Biol Reprod 63: 846-850, 2000.
174. Read CP, Word RA, Ruscheinsky MA, Timmons BC, Mahendroo MS. Cervical remodeling during pregnancy and parturition: molecular characterization of the softening phase in mice. Reproduction 134: 327-340, 2007.
175. Rechberger T, Woessner JF Jr. Collagenase, its inhibitors, and decorin in the lower uterine segment in pregnant women. Am J Obstet Gynecol 168: 1598-1603, 1993.
176. Reinheimer TM. Barusiban suppresses oxytocin-induced preterm labor in non-human primates. BMC Pregnancy Childbirth 7, Suppl 1: S15, 2007.
177. Reinheimer TM, Chellman GJ, Resendez JC, Meyer JK, Bee WH. Barusiban, an effective long-term treatment of oxytocin-induced preterm labor in nonhuman primates. Biol Reprod 75: 809-814, 2006.
178. Riemer RK, Buscher C, Bansal RK, Black SM, He Y, Natuzzi ES. Increased expression of nitric oxide synthase in the myometrium of the pregnant rat uterus. Am J Physiol Endocrinol Metab 272: E1008-E1015, 1997.
179. Rocca MS, Wehner NG. The guinea pig as an animal model for developmental and reproductive toxicology studies. Birth Defects Res B Dev Reprod Toxicol 86: 92-97, 2009.
180. Rodriguez HA, Ortega HH, Ramos JG, Munoz-de-Toro M, Luque EH. Guinea-pig interpubic joint (symphysis pubica) relaxation at parturition: underlying cellular processes that resemble an inflammatory response. Reprod Biol Endocrinol 1: 113, 2003.
181. Romero R, Espinoza J, Goncalves LF, Kusanovic JP, Friel LA, Nien JK. Inflammation in preterm and term labour and delivery. Semin Fetal Neonatal Med 11: 317-326, 2006.
182. Romero R, Espinoza J, Kusanovic JP, Gotsch F, Hassan S, Erez O, Chaiworapongsa T, Mazor M. The preterm parturition syndrome. BJOG 113, Suppl 3: 17-42, 2006.
183. Romero R, Mazor M, Brandt F, Sepulveda W, Avila C, Cotton DB, Dinarello CA. Interleukin-1 alpha and interleukin-1 beta in preterm and term human parturition. Am J Reprod Immunol 27: 117-123, 1992.
184. Romero R, Mazor M, Sepulveda W, Avila C, Copeland D, Williams J. Tumor necrosis factor in preterm and term labor. Am J Obstet Gynecol 166: 1576-1587., 1992.
185. Romero R, Mazor M, Tartakovsky B. Systemic administration of interleukin-1 induces preterm parturition in mice. Am J Obstet Gynecol 165: 969-971, 1991.
186. Romero R, Scoccia B, Mazor M, Wu YK, Benveniste R. Evidence for a local change in the progesterone/estrogen ratio in human parturition at term. Am J Obstet Gynecol 159: 657-660, 1988.
187. Romero R, Sibai BM, Sanchez-Ramos L, Valenzuela GJ, Veille JC, Tabor B, Perry KG, Varner M, Goodwin TM, Lane R, Smith J, Shangold G, Creasy GW. An oxytocin receptor antagonist (atosiban) in the treatment of preterm labor: a randomized, double-blind, placebo-controlled trial with tocolytic rescue. Am J Obstet Gynecol 182: 1173-1183, 2000.
188. Romero R, Tartakovsky B. The natural interleukin-1 receptor antagonist prevents interleukin-1-induced preterm delivery in mice. Am J Obstet Gynecol 167: 1041-1045, 1992.
189. Romero R, Yoon BH, Kenney JS, Gomez R, Allison AC, Sehgal PB. Amniotic fluid interleukin-6 determinations are of diagnostic and prognostic value in preterm labor. Am J Reprod Immunol 30: 167-183, 1993.
190. Rouse DJ, Caritis SN, Peaceman AM, Sciscione A, Thom EA, Spong CY, Varner M, Malone F, Iams JD, Mercer BM, Thorp J, Sorokin Y, Carpenter M, Lo J, Ramin S, Harper M, Anderson G. A trial of 17 alpha-hydroxyprogesterone caproate to prevent prematurity in twins. N Engl J Med 357: 454-461, 2007.
191. Russell WMS, Burch RL. The Principles of Human Experimental Technique. London: Methuen, 1959.
192. Sabeur K, Edwards DP, Meizel S. Human sperm plasma membrane progesterone receptor(s) and the acrosome reaction. Biol Reprod 54: 993-1001, 1996.
193. Sadowsky DW, Adams KM, Gravett MG, Witkin SS, Novy MJ. Preterm labor is induced by intraamniotic infusions of interleukin-1beta and tumor necrosis factor-alpha but not by interleukin-6 or interleukin-8 in a nonhuman primate model. Am J Obstet Gynecol 195: 1578-1589, 2006.
194. Sadowsky DW, Haluska GJ, Gravett MG, Witkin SS, Novy MJ. Indomethacin blocks interleukin 1beta-induced myometrial contractions in pregnant rhesus monkeys. Am J Obstet Gynecol 183: 173-180, 2000.
195. Sadowsky DW, Novy MJ, Witkin SS, Gravett MG. Dexamethasone or interleukin-10 blocks interleukin-1beta-induced uterine contractions in pregnant rhesus monkeys. Am J Obstet Gynecol 188: 252-263, 2003.
196. Samalecos A, Gellersen B. Systematic expression analysis and antibody screening do not support the existence of naturally occurring progesterone receptor (PR)-C, PR-M, or other truncated PR isoforms. Endocrinology 149: 5872-5887, 2008.
197. Schellenberg JC. Oxytocin in parturition of guinea pigs, humans, and other species. Prog Brain Res 139: 299-308, 2002.
198. Schellenberg JC. The effect of oxytocin receptor blockade on parturition in guinea pigs. J Clin Invest 95: 13-19, 1995.
199. Schmid B, Wong S, Mitchell BF. Transcriptional regulation of oxytocin receptor by interleukin-1beta and interleukin-6. Endocrinology 142: 1380-1385., 2001.
200. Schmitz T, Souil E, Herve R, Nicco C, Batteux F, Germain G, Cabrol D, Evain-Brion D, Leroy MJ, Mehats C. PDE4 inhibition prevents preterm delivery induced by an intrauterine inflammation. J Immunol 178: 1115-1121, 2007.
201. Schofield BM. The acute effect of progestational compounds on intact rabbit myometrium. J Physiol 157: 117-123, 1961.
202. Shennan AH, Chandiramani M. Antibiotics for spontaneous preterm birth. BMJ 337: a3015, 2008.
203. Sibley CP, Bauman KF, Firth JA. Permeability of the foetal capillary endothelium of the guinea-pig placenta to haem proteins of various molecular sizes. Cell Tissue Res 223: 165-178, 1982.
204. Sibley CP, Ward BS, Glazier JD, Moore WM, Boyd RD. Electrical activity and sodium transfer across in vitro pig placenta. Am J Physiol Regul Integr Comp Physiol 250: R474-R484, 1986.
205. Smith R, Smith JI, Shen X, Engel PJ, Bowman ME, McGrath SA, Bisits AM, McElduff P, Giles WB, Smith DW. Patterns of plasma corticotrophin-releasing hormone, progesterone, estradiol, and estriol change and the onset of human labor. J Clin Endocrinol Metab 94: 2066-2074, 2009.
206. 2+ sensitivity of smooth muscle and nonmuscle myosin II: modulated by G proteins, kinases, and myosin phosphatase. Physiol Rev 83: 1325-1358, 2003.
207. Stabenfeldt GH, Drost M, Franti CE. Peripheral plasma progesterone levels in the ewe during pregnancy and parturition. Endocrinology 90: 144-150, 1972.
208. 2+ desensitization. Mol Cell Biochem 127-128: 229-237, 1993.
209. Sugimoto Y, Yamasaki A, Segi E, Tsuboi K, Aze Y, Nishimura T, Oida H, Yoshida N, Tanaka T, Katsuyama M, Hasumoto K, Murata T, Hirata M, Ushikubi F, Negishi M, Ichikawa A, Narumiya S. Failure of parturition in mice lacking the prostaglandin F receptor. Science 277: 681-683, 1997.
210. Taggart MJ, Marston SB. The effects of vascular smooth muscle caldesmon on force production by "desensitised" skeletal muscle fibres. FEBS Lett 242: 171-174, 1988.
211. Tahara M, Kawagishi R, Sawada K, Morishige K, Sakata M, Tasaka K, Murata Y. Tocolytic effect of a Rho-kinase inhibitor in a mouse model of lipopolysaccharide-induced preterm delivery. Am J Obstet Gynecol 192: 903-908, 2005.
212. Takayanagi Y, Yoshida M, Bielsky IF, Ross HE, Kawamata M, Onaka T, Yanagisawa T, Kimura T, Matzuk MM, Young LJ, Nishimori K. Pervasive social deficits, but normal parturition, in oxytocin receptor-deficient mice. Proc Natl Acad Sci USA 102: 16096-16101, 2005.
213. Terzidou V, Lee Y, Lindström T, Johnson M, Thornton S, Bennett PR. Regulation of the human oxytocin receptor by nuclear factor-kappaB and CCAAT/enhancer-binding protein-beta. J Clin Endocrinol Metab 91: 2317-2326, 2006.
214. Thong KJ, Baird DT. Induction of abortion with mifepristone and misoprostol in early pregnancy. Br J Obstet Gynaecol 99: 1004-1007, 1992.
215. Tulchinsky D, Hobel CY, Yeager E, Marshall YR. Plasma estrone, estradiol, estriol, progesterone, and 17-hydroxyprogesterone in human pregnancy. 1. Normal pregnancy. Am J Obstet Gynecol 112: 1095-1100, 1972.
216. Turnbull AC, Patten PT, Flint AP, Keirse MJ, Jeremy JY, Anderson AB. Significant fall in progesterone and rise in oestradiol levels in human peripheral plasma before onset of labor. Lancet 1: 101-103, 1974.
217. Uldbjerg N, Malmstrom A, Ekman G, Sheehan J, Ulmsten U, Wingerup L. Isolation and characterization of dermatan sulphate proteoglycan from human uterine cervix. Biochem J 209: 497-503, 1983.
218. Van Look PF, Bygdeman M. Antiprogestational steroids: a new dimension in human fertility regulation. Oxf Rev Reprod Biol 11: 2-60, 1989.
219. Virgo BB, Bellward GD. Serum progesterone levels in the pregnant and postpartum laboratory mouse. Endocrinology 95: 1486-1490, 1974.
220. Wang H, Xie H, Dey SK. Loss of cannabinoid receptor CB1 induces preterm birth. PLoS One 3: e3320, 2008.
221. Weiner CP, Mason C, Hall G, Ahmad U, Swaan P, Buhimschi IA. Pregnancy and estradiol modulate myometrial G-protein pathways in the guinea pig. Am J Obstet Gynecol 195: 275-287, 2006.
222. Welsh T, Caritis SN, Mesiano S, Zakar. Parturition in the guinea pig is preceded by a fall in uterine progesterone receptor levels (Abstract). Reprod Sci 16: 185, 2009.
223. Wentz MJ, Shi SQ, Shi L, Salama SA, Harirah HM, Fouad H, Garfield RE, Al-Hendy A. Treatment with an inhibitor of catechol-O-methyltransferase activity reduces preterm birth and impedes cervical resistance to stretch in pregnant rats. Reproduction 134: 831-839, 2007.
224. Wood NS, Marlow N, Costeloe K, Gibson AT, Wilkinson AR. Neurologic and developmental disability after extremely preterm birth. EPICure Study Group. N Engl J Med 343: 378-384, 2000.
225. i sensitivity of human myometrium. Am J Obstet Gynecol 190: 222-228, 2004.
226. Word RA, Kamm KE, Casey ML. Contractile effects of prostaglandins, oxytocin, and endothelin-1 in human myometrium in vitro: refractoriness of myometrial tissue of pregnant women to prostaglandins E2 and F2 alpha. J Clin Endocrinol Metab 75: 1027-1032, 1992.
227. Word RA, Li XH, Hnat M, Carrick K. Dynamics of cervical remodeling during pregnancy and parturition: mechanisms and current concepts. Semin Reprod Med 25: 69-79, 2007.
228. Xu H, Gonzalez JM, Ofori E, Elovitz MA. Preventing cervical ripening: the primary mechanism by which progestational agents prevent preterm birth? Am J Obstet Gynecol 198: 314.e1-314.e8, 2008.
229. Yellon SM, Ebner CA, Sugimoto Y. Parturition and recruitment of macrophages in cervix of mice lacking the prostaglandin F receptor. Biol Reprod 78: 438-444, 2008.
230. Young WS 3rd, Shepard E, AIMCO J, Hennighausen L, Wagner KU, LaMarca ME, McKinney C, Ginns EI. Deficiency in mouse oxytocin prevents milk ejection, but not fertility or parturition. J Neuroendocrinol 8: 847-853, 1996.
231. Zarrow MX, Anderson NC Jr, Callantine MR. Failure of progestogens to prolong pregnancy in the guinea pig. Nature 198: 690-692, 1963.
232. Zhao B, Koon D, Curtis AL, Soper J, Bethin KE. Identification of 9 uterine genes that are regulated during mouse pregnancy and exhibit abnormal levels in the cyclooxygenase-1 knockout mouse. Reprod Biol Endocrinol 5: 28, 2007.