Dynamics and plasticity of peptidergic control centres in the retino-brain-pituitary system of Xenopus laevis

Microscopy Research and Technique

Volumn 54, Issue 3, 2001, Pages 188-199

  Kramer, B M R ^a   Kolk, S M ^a   Berghs, C A F M ^a,b   Tuinhof, R ^a,c   Ubink, R ^a,d   Jenks, B G ^a   Roubos, E W ^a  

^a RADBOUD UNIVERSITY NIJMEGEN   (Netherlands)

^b CURAGEN CORPORATION   (United States)

^c UNIVERSITY OF FRIBOURG   (Switzerland)

^d NV ORGANON   (Netherlands)

Author keywords

Melanotrope cell; Pars intermedia; Retino brain pituitary system; Xenopus laevis

Indexed keywords

PHYSIOLOGY; SIGNAL TRANSDUCTION; TRANSCRIPTION;

BACKGROUND ADAPTATION; CONTROL CENTRE; ENVIRONMENTAL FACTORS; FUNCTIONAL ASPECTS; INTERMEDIA; MELANOTROPE CELL; PAR INTERMEDIUM; RETINO-BRAIN-PITUITARY SYSTEM; STRUCTURAL ASPECTS; XENOPUS LAEVIS;

PEPTIDES;

4 AMINOBUTYRIC ACID; ALPHA INTERMEDIN; CALCIUM ION; DOPAMINE; NEUROPEPTIDE Y; PROOPIOMELANOCORTIN;

ARTICLE; CALCIUM SIGNALING; DYNAMICS; EXOCYTOSIS; HYPOPHYSIS INTERMEDIATE LOBE; HYPOTHALAMUS HYPOPHYSIS SYSTEM; LIGHT; LOCUS CERULEUS; MAGNOCELLULAR NUCLEUS; NERVE CELL PLASTICITY; NONHUMAN; PEPTIDERGIC NERVOUS SYSTEM; PRIORITY JOURNAL; PROTEIN PROCESSING; RAPHE NUCLEUS; RETINA; SECOND MESSENGER; SIGNAL TRANSDUCTION; SUPRACHIASMATIC NUCLEUS; SYNAPSE; TEMPERATURE; XENOPUS LAEVIS;

ANURA; MELANOPHORA; XENOPUS LAEVIS;

EID: 0035426196     PISSN: 1059910X     EISSN: None     Source Type: Journal    
DOI: 10.1002/jemt.1132     Document Type: Article

References (149)

1. Allaerts W, Ubink R, De Vente J, Tuinhof R, Jenks BG, Roubos, EW. 1997. Nitric oxide synthase and background adaptation in Xenopus laevis. J Chem Neuroanat 14:21-31.
2. Andersen AC, Tonon M-C, Pelletier G, Conlon JM, Fasolo A, Vaudry H. 1993. Neuropeptides in the amphibian brain. Int Rev Cytol 138:89-210.
3. Artero C, Fasolo A, Andreone C, Franzoni MF. 1994. Multiple sources of the pituitary pars intermedia innervation in amphibians: a DiI retrograde tract-tracing study. Neurosci Lett 169:163-166.
4. Ayoubi TAY. 1991. Expression of proopiomelanocortin and 7B2 genes in the pituitary of Xenopus laevis. PhD thesis. University of Nijmegen.
5. Ayoubi TAY, van Duijnboven HLP, Coenen AJM, Jenks BG, Roubos EW, Martens GJM. 1991. Coordinated expression of 7B2 and αMSH in the melanotrope cells of Xenopus laevis: an immunocytochemical and in situ hybridization study. Cell Tiss Res 264:329-334.
6. Ayoubi TAY, Jenks BG, Roubos EW, Martens GJM. 1992. Transcriptional and posttranscriptional regulation of the proopiomelanocortin gene in the pars intermedia of the pituitary gland of Xenopus laevis. Endocrinology 130:3560-3566.
7. Bagnara JT, Hadley ME, editors. 1973. Chromatophores and colour change. The comparative physiology of animal pigmentation. Englewood Cliffs, NJ: Prentice Hall Inc.
8. Battaglia AA, Feuilloley M, Mulatero B, Beltramo M, Thibault J, Franzoni F, Calas A, Vaudry H, Fasolo A. 1995. Confocal microscopy analysis of NPY and TH immunoreactivities in the hypothalamo-hypophysial system of the frog. NeuroReport 6:645-649.
9. Berghs CAFM, Roubos EW. 1996. Background adaptation and synapse plasticity in the pars intermedia of Xenopus laevis. Neuroscience 70:833-841.
10. Berghs CAFM, Tanaka S, van Strien FJC, Kurabuchi S, Roubos EW. 1997. The secretory granule and pro-opiomelanocortin processing in Xenopus melanotrope cells during background adaptation. J Histochem Cytochem 45:1673-1682.
11. Berghs CAFM, Tanaka S, Roubos EW. 1998. Neuroendocrine responses in background adaptation. In: Vaudry H, Tonon MC, Roubos EW, De Loof A, editors. Trends in comparative endocrinology and neurobiology. From molecular to integrative biology. Ann NY Acad Sci 839:574-575.
12. Berghs CAFM, Korteweg N, Bouteiller A, Tuinhof R, Asbreuk C, Verhage M, Roubos EW. 1999. Co-expression in Xenopus neurons and neuroendocrine cells of messenger RNA homologues of exocytosis proteins DOC2 and munc18-1. Neuroscience 92:763-772.
13. Blomqvist AG, Roubos EW, Larhammar D, Martens GJM. 1995. Cloning and sequence analysis of a neuropeptide Y/peptide YY receptor Y1 cDNA from Xenopus laevis. Biochim Biophys Acta 1261:439-441.
14. Braks JAM. 1995. The role of the neuroendocrine polypeptide 7B2. PhD thesis. University of Nijmegen.
15. Braks JAM, Martens GJM. 1994. 7B2 is a neuroendocrine chaperone that transiently interacts with prohormone convertase PC2 in the secretory pathway. Cell 78:263-273.
16. Braks JAM, Martens GJM. 1995. The neuroendocrine chaperone 7B2 can enhance in vitro POMC cleavage by prohormone convertase PC2. FEBS Lett 371:154-158.
17. Braks JAM, Guldemond KCW, van Riel MCHM , Coenen AJM, Martens GJM. 1992. Structure and expression of Xenopus prohormone convertase PC2. Fed Eur Biochem Soc Lett 305:45-50.
18. A versus GABAB receptor inhibition of the melanotrope cell of Xenopus laevis. Endocrinology 138:203-212.
19. Cornelisse LN, Scheenen WJJM, Koopman WJH, Roubos EW, Gielen CCAM. 2000. Minimal model for intracellular calcium oscillations and electrical bursting in melanotrope cells of Xenopus laevis. Neur Comp 12:1-25.
20. Danger JM, Guy J, Benyamina M, Jégou S, Leboulenger F, Coté J, Tonon MC, Pelletier G, Vaudry H. 1985. Localization and identification of neuropeptide Y (NPY)-like immunoreactivity in the frog brain. Peptides 6 1225-1236.
21. Deen PMT, Terwel D, Bussemakers MJM, Roubos EW, Martens GJM. 1991. Structural analysis of the entire proopiomelanocortin gene B of Xenopus laevis. Eur J Biochem 201:129-137.
22. Deen PMT, Bussemakers MJM, Terwel D, Roubos EW, Martens GJM. 1992. Comparative structural analysis of the transcriptionally active proopiomelanocortin genes A and B of Xenopus laevis. Mol Biol Evol 9:483-494.
23. B receptor function in the in vitro and in vivo regulation of α-MSH secretion from melanotrope cells of Xenopus laevis. Endocrinology 132:674-682.
24. De Rijk EPCT, Jenks BG, Vaudry H, Roubos EW. 1990a. GABA and NPY coexist in axons innervating the neurointermediate lobe of the pituitary of Xenopus laevis. Neuroscience 38:495-502.
25. De Rijk EPCT, Jenks BG, Wendelaar Bonga SE. 1990b. Morphology of the pars intermedia and the melanophore-stimulating cells in Xenopus laevis in relation to background adaptation. Gen Comp Endocrinol 79:74-82.
26. De Rijk EPCT, van Strien FJC, Roubos EW. 1992. Demonstration of coexisting catecholamine (dopamine), amino acid (GABA) and peptide (NPY) involved in inhibition of melanotrope cell activity in Xenopus laevis. J Neurosci 12:864-871.
27. Dierickx K. 1967. The function of the hypophysis without preoptic neurosecretory control Z Zellforsch 78:114-130.
28. Dores RM, Steveson TC, Lopez L. 1991. Differential mechanisms for the N-acetylation of alpha-melanocyte-stimulating hormone and beta-endorphin in the intermediate pituitary of the frog, Xenopus laevis. Neuroendocrinology 53:54-62.
29. Dotman CH. 1998. Proopiomelanocortin gene expression in Xenopus laevis melanotrope cells. Differential regulation by neuronal factors and role of second messengers. Enschede: Print Partners Ipskamp. 117 pp.
30. Dotman CH, Cruijsen PMJM, Jenks BG, Roubos EW. 1996. Differential action of secreto-inhibitors on pro-opiomelanocortin biosynthesis in the intermediate pituitary of the amphibian Xenopus laevis. Endocrinology 137:4551-4557.
31. Dotman CH, Maia A, Jenks BG, Roubos EW. 1997. Sauvagine and TRH differentially stimulate proopiomelanocortin biosynthesis in the Xenopus laevis intermediate pituitary. Neuroendocrinology 66: 106-113.
32. Dotman CH, van Herp F, Martens GJM, Jenks BG, Roubos EW. 1998a. Dynamics of proopiomelanocortin and prohormone convertase (PC2) gene expression in Xenopus melanotrope cells during long-term background adaptation. J Endocrinol 159:281-286.
33. Dotman CH, Maia A, Cruijsen PMJM, Jenks BG, Roubos EW. 1998b. Inhibitory and stimulatory control of proopiomelanocortin biosynthesis in the intermediate pituitary of Xenopus laevis. In: Vaudry H, Tonon MC, Roubos EW, De Loof A, editors. Trends in comparative endocrinology and neurobiology. From molecular to integrative biology. Ann NY Acad Sci 839:472-474.
34. Eagleson GW, Ubink R, Jenks BG, Roubos EW. 1998. Forebrain differentiation and axonogenesis in amphibians: I. Differentiation of the suprachiasmatic nucleus in relation to background adaptation behavior. Brain Behav Evol 52:23-36.
35. Eipper BA, Mains RE. 1980. Structure and biosynthesis of pro-adrenocorticotropin/ endorphin and related peptides. Endocrine Rev 1:1-27.
36. Fasolo A, Andreone C, Vandesande F. 1984. Immunohistochemical localization of corticotropin releasing factor (CRF)-like immunoreactivity in the hypothalamus of the newt, Triturus cristatus. Neuroscience Lett 49:135-142.
37. González A, Smeets WJAJ. 1992. Distribution of vasotocin- and mesotocin-like immunoreactivities in the brain of the South African clawed frog Xenopus laevis. J Chem Neuroanat 5:465-479.
38. González A, Smeets WJAJ. 1993. Noradrenaline in the brain of the South African clawed frog Xenopus laevis. A study with antibodies against noradrenaline and dopamine-β-hydroxylase. J Comp Neurol 331:363-374.
39. González A, Tuinhof R, Smeets WJAJ. 1993. Distribution of tyrosine hydroxylase- and dopamine-immunoreactivities in the brain of the South African clawed frog Xenopus laevis. Anat Embryol 187:193-201.
40. Gonzalez GC, Lederis K. 1988. Sauvagine-like and corticotropin-releasing factor-like immunoreactivity in the brain of the bullfrog (Rana catesbeiana). Cell Tissue Res 253:29-37.
41. Goos HJTh. 1978. Hypophysiotropic centers in the brain of amphibians and fish. Am Zool 18:401-410.
42. Hadley ME, editor. 1988. The melanotropic peptides. Boca Raton, FL: CRC Press.
43. Hanson PI, Heuser JE, Jahn R. 1997. Neurotransmitter release: four years of SNARE complexes. Curr Opin Neurobiol 7:310-315.
44. Hogben L, Slome D. 1931. The pigmentary effector system: the dual character of endocrine coordination in amphibian colour change. Proc R Soc London B108:10-53.
45. Holthuis JCM. 1996. The secretory pathway in peptide hormone-producing cells. PhD thesis. University of Nijmegen.
46. Holthuis JCM, Jansen EJR, van Riel MCHM, Martens GJM. 1995. Molecular probing of the secretory pathway in peptide hormone-producing cells. J Cell Sci 108:3295-3305.
47. Hopkins CR. 1970. Studies on secretory activity in the pars intermedia of Xenopus laevis. 1. Fine structural changes related to the onset of secretory activity in vivo. Tissue Cell 2:59-70.
48. Iturriza FC. 1969. Further evidences for the blocking effect of catecholamines on the secretion of melanocyte-stimulating hormone in toads. Gen Comp Endocrinol 12:417-426.
49. Jahn R, Südhof TC. 1999. Membrane fusion and exocytosis. Annu Rev Biochem 68:863-911.
50. Jenks BG, van Zoest ID. 1990. Melanotrope cell function in the neuroendocrine regulation of dermal melanophores. In: Hanke W, editor. Fortschritte der Zoologie, Biology and Physiology of Amphibians, Vol 38. W. Stuttgart, New York: Gustav Fischer Verlag. p 219-228.
51. Jenks BG, Verburg-van Kemenade BML. 1988. Neuroendocrine integration in the pars intermedia of the pituitary gland of the amphibian Xenopus laevis. In: Proceedings of the Serbian academy of sciences. Pantic V, editor. Bulletin 29:37-55.
52. Jenks BG, Overbeeke AP, McStay BF. 1977. Synthesis, storage and release of MSH in the pars intermedia of the pituitary gland of Xenopus laevis during background adaptation. Can J Zool 55:922-927.
53. Jenks BG, Verburg-van Kemenade BML, Martens GJM. 1988. Proopiomelanocortin in the amphibian pars intermedia: a neuroendocrine model system. In: Hadley ME, editor. The melanotropic peptides, Vol 1: source, synthesis, chemistry, circulation and metabolism. Boca Raton, FL: CRC Press. p 103-126.
54. B receptor agonist baclofen inhibits cyclic-AMP production in melanotrope cells of Xenopus laevis. Life Sci 48:1633-1637.
55. Jenks BG, de Koning HP, Cruijsen, PMJM, Mauger CMA, Roubos EW, Tonon MC, Desrues L, Vaudry H. 1993a. Analysis of inositol metabolism in intermediate lobes of Xenopus laevis in relation to background adaptation. Ann NY Acad Sci 680:188-198.
56. Jenks BG, de Koning HP, Valentijn K, Roubos EW. 1993b. Dual action of GABAA receptors on the secretory process of melanotrophs of Xenopus laevis. Neuroendocrinology 58:80-85.
57. Jenks BG, Leenders HJ, Martens GJM, Roubos EW. 1993c. Adaptation physiology: the functioning of pituitary melanotrope cells during background adaptation of the amphibian Xenopus laevis. Zool Sci 10:1-11.
58. Jenks BG, Lieste JR, Koopman WJH, Scheenen WJJM, Roubos EW. 1999. Calcium currents steps and waves: the Xenopus melanotrope cell as a model to study calcium signaling. In: Roubos EW, Wendelaar Bonga SE, Vaudry H, De Loof A, editors. Recent developments in comparative endocrinology and neurobiology. Maastricht: Shaker Publishing. p 193-196.
59. Kolk SM, Nordquist R, Tuinhof R, Gagliardini L, Cools AR, Roubos EW. 1999. Physiologically regulated levels of the exocytosis protein SNAP-25 in Xenopus neuroendocrine cells. In: Roubos EW, Wendelaar Bonga SE, Vaudry H, De Loof A, editors. Recent developments in comparative endocrinology and neurobiology. Maastricht: Shaker Publishing. p 64-65
60. Kolk SM, Nordquist R, Tuinhof R, Gagliardini L, Thompson B, Cools AR, Roubos EW. 2000. Localization and physiological regulation of the exocytosis protein SNAP-25 in the brain and pituitary cells of Xenopus laevis. J Neuroendocrinol 12:694-70.
61. Kolk SM, Berghs CAFM, Vaudry H, Verhage M, Roubos EW. 2001. Physiological control of expression of munc18-1 homologue in melanotrope cells of Xenopus laevis. Endocrinology 142:1950-1957.
62. Kongsamut S, Shibuya I, Uehara M, Douglas WW. 1993. Melanotrophs of Xenopus laevis do respond directly to neuropeptide Y as evidenced by reductions in secretion and cytosolic calcium pulsing in isolated cells. Endocrinology 133:336-342.
63. Koopman WJH, Jenks BG, Roubos EW, Scheenen WJJM. 1996. Retrieving spatiotemporal information from confocal data: a study using melanotrope cells of Xenopus laevis. In: Slavik J, editor. Fluorescence microscopy and fluorescent probes. New York: Plenum Press. p 300-305.
64. 2+-waves in Xenopus melanotropes depend on calcium-induced calcium release: a fluorescence correlation microscopy and linescanning study. Cell Calcium 26:59-67.
65. Kramer BMR, Welting J, Jansen M, Claassen I, Jenks BG, Roubos EW. 1999. Regulation of suprachiasmatic melanotrope inhibiting neurons in Xenopus laevis. In: Roubos EW, Wendelaar Bonga SE, Vaudry H, De Loof A, editors. Recent developments in comparative endocrinology and neurobiology. Maastricht: Shaker Publishing. p 281-282.
66. Kramer BMR, Berghs CAFM, Welting J, Jenks BG, Roubos EW. 2001. Functional organization of the suprachiasmatic nucleus of Xenopus laevis in relation to background adaptation. J Comp Neurol 432:346-355.
67. Lázár G, Maderdrut JL, Trasti SL, Liposits Z, Tóth P, Kozicz T, Merchenthaler I. 1993. Distribution of proneuropeptide Y-derived peptides in the brain of Rana esculenta and Xenopus laevis. J Comp Neurol 327:551-571.
68. Lederis K. 1987. Non-mammalian corticotropin release-stimulating peptides. Ann NY Acad Sci 512:129-138.
69. Leenders HJ, de Koning HP, Jenks BG, Roubos EW. 1993. Differential effects of dopamine, GABA and NPY on the melanotrope cells of Xenopus laevis. Life Sci 52:1969-1975.
70. Leroux P, Tonon M-C Jégou S, Leboulenger F, Delarue C, Perroteau I, Netchitailo P, Kupryzewski G, Vaudry H. 1982. In vitro study of frog (Rana ridibunda Pallas) neurointermediate lobe secretion by use of a simplified perifusion system. I. Effect of TRH analogues uppon α-MSH release. Gen Comp Endocrinol 46:13-23
71. Lieste JR, Scheenen WJJM, Willems PHGM, Jenks BG, Roubos EW. 1996. Calcium oscillations in melanotrope cells of Xenopus laevis are regulated by cAMP-dependent mechanisms. Cell Calcium 20: 329-337.
72. Lieste JR, Scheenen WJJM, Jenks BG, Roubos EW. 1998a. Single cell secretion measurements in Xenopus laevis. In: Vaudry H, Tonon M-C, Roubos EW, De Loof A, editors. Trends in comparative endocrinology and neurobiology. From molecular to integrative biology. Ann NY Acad Sci 839:546-548.
73. 2+ patterns in a neuroendocrine cell. J Biol Chem 273:25686-25694.
74. Loh YP, Gainer H. 1977. Biosynthesis, processing and control of release of melanotropic peptides in the neurointermediate lobe of Xenopus laevis. J Gen Physiol 70:37-58.
75. Loh, YP, Myers B, Wong B, Parish DC, Lang M, Goldman ME. 1985. Regulation of pro-opiomelanocortin synthesis by dopamine and cAMP in the amphibian pituitary intermediate lobe. J Biol Chem 260:8956-8963.
76. Martens GJM. 1986. Expression of two proopiomelanocortin genes in the pituitary gland of Xenopus laevis: complete structures of the two preprohormones. Nucleic Acids Res 14:3791-3798.
77. Martens GJM. 1987. Structural organization of the proopiomelanocortin gene in Xenopus laevis: 5′ end homologies with the toad and mammalian genes. Eur J Biochem 165:467-472.
78. Martens GJM, Jenks BG, van Overbeeke AP. 1981. N-α-acetylation is linked to α-MSH release from pars intermedia of the amphibian pituitary glands. Nature 294:558-560.
79. Martens GJM, Civelli O, Herbert E. 1985. Nucleotide sequence of cloned cDNA for pro-opiomelanocortin in the amphibian Xenopus laevis. J Biol Chem 260:13685-13689.
80. Martens GJM, Weterings KAP, van Zoest ID, Jenks BG. 1987. Physiologically-induced changes in proopiomelanocortin mRNA levels in the pituitary gland of the amphibian Xenopus laevis. Biochem Biophys Res Commun 143:678-684.
81. Martens GJM, Bussemakers MJG, Ayoubi TAY, Jenks BG. 1989. The novel pituitary polypeptide 7B2 is a highly-conserved protein coexpressed with proopiomelanocortin. Eur J Biochem 181:75-79.
82. Martens GJM, Molhuizen H, Gröneveld D, Roubos EW. 1991. Cloning and sequence analysis of brain cDNA encoding a Xenopus D2 dopamine receptor. FEBS Lett 281:85-89.
83. Maruthainar K, Loh YP, Smyth DG. 1992. The processing of β-endorphin and α-melanotropin in the pars intermedia of Xenopus laevis is influenced by background adaptation. Endocrinology 135:469-478.
84. Mimnagh KL, Bolaffi JL, Montgomery NM, Kaltenbach JC. 1987. Thyrotropin-releasing hormone (TRH): immunohistochemical distribution in tadpole and frog brain. Gen Comp Endocrinol 66: 394-404.
85. Nieuwkoop PD, Faber J. 1967. Normal table of Xenopus laevis (Daudin). Amsterdam: North Holland.
86. Nyholm NEI. 1977 Some morphogenetic features of the adenohypophyseal primordium of early Xenopus laevis tadpoles. Cell Tiss Res 180:223-230.
87. Nyholm NEI, Doerr-Schott J. 1977. Developmental immunohistology of melanotrophs in Xenopus laevis tadpoles. Cell Tissue Res 18: 231-239.
88. Olivereau M, Vandesande F, Boucique E, Ollevier F, Olivereau JM. 1987. Immunohistochemical localization and spatial relation to the adenohypophysis of a somatostatin-like and a corticotropin-releasing factor-like peptide in the brains of four amphibian species. Cell Tissue Res 247:317-324.
89. Oshima K, Gorbman A. 1969. Evidence for a doubly innervated secretory unit in the anuran pars intermedia. I. Electrophysiological studies. Gen Comp Endocrinol 13:98-107.
90. Pasquier DA, Cannata MA, Tramezzani JH. 1980. Central connections of the toad neural lobe as shown by retrograde neuronal labeling; classical and new connections. Brain Res 195:37-45.
91. Pehleman F-W. 1967.Ultrastructure and innervation of the pars intermedia of the pituitary of Xenopus laevis. Gen Comp Endocrinol 9:481.
92. Roubos EW. 1992. Routing and release of input and output messengers of peptidergic systems. In: Progress in brain research. Joosse J, Buijs RM, Tilders FJH, editors. Amsterdam: Elsevier. Vol 92. pp 257-265.
93. Roubos EW. 1997. Background adaptation by Xenopus laevis: a model for studying neuronal information processing in the pituitary pars intermedia. Comp Biochem Physiol 118A:533-550.
94. Roubos EW, Berghs CAFM. 1993. Effects of background adaptation on αMSH and β-endorphin in secretory granule types of melanotrope cells of Xenopus laevis. Cell Tiss Res 274:587-596.
95. Roubos EW, Martens GJM, Jenks BG. 1993. Control of melanotrope cell activity in Xenopus laevis. Ann NY Acad Sci 680:130-134.
96. Roubos EW, Wendelaar Bonga SE, Vaudry H, De Loof A, editors. 1999. Recent developments in comparative endocrinology and neurobiology, Maastricht: Shaker Publishing. 378 pp.
97. Rouillé Y, Michel G, Chauvet MT, Chauvet J, Acher, R 1989. Particular processing of pro-opiomelanocortin in Xenopus laevis intermediate pituitary. Fed Eur Biochem Soc 1:215-218.
98. Scheenen WJJM. 1995. Calcium dynamics in melanotrope cells of Xenopus laevis. PhD thesis. University of Nijmegen.
99. Scheenen WJJM, Jenks BG, Willems PHGM, Roubos EW. 1993. Spontaneous calcium oscillations in melanotrope cells of Xenopus laevis. Ann NY Acad Sci 680:603-605.
100. Scheenen WJJM, Jenks BG, Roubos EW, Willems PHGM. 1994a Spontaneous calcium oscillations in Xenopus laevis melanotrope cells are mediated by N-type calcium channels. Cell Calcium 15: 36-44.
101. Scheenen WJJM, Jenks BG, Willems PHGM, Roubos EW. 1994b. Action of stimulatory and inhibitory α-MSH secretagogues on spontaneous calcium oscillations in melanotrope cells of Xenopus laevis. Pflügers Arch 427:244-251.
102. Scheenen WJJM, de Koning HP, Jenks, BG, Vaudry H, Roubos EW. 1994c. The secretion of α-MSH from Xenopus melanotropes depends on calcium influx through N-type voltage-operated calcium channels. J Neuroendocrinol 6:457-464.
103. 2+ oscillations, cyclic AMP and secretion in melanotrope cells of Xenopus laevis via a Y1 receptor. Peptides 16:889-895.
104. 2+ oscillations in Xenopus laevis melanotrope cells. Cell Calcium 19:219-227.
105. i oscillations does exocytosis occur in isolated Xenopus melanotropes? In: Roubos EW, Wendelaar Bonga SE, Vaudry H, De Loof A, editors. Recent developments in comparative endocrinology and neurobiology. Maastricht: Shaker Publishing. p 113-115.
106. Seki T, Nakai Y, Shioda S, Mitsuma T, Kikuyama S. 1983. Distribution of immunoreactive thyrotropin-releasing hormone in the forebrain and hypophysis of the bullfrog Rana catesbeiana. Cell Tiss Res 233:507-516.
107. Shibuya I, Douglas WW. 1993a. Measurements of cytosolic free calcium in melanotrophs of Xenopus laevis: Indications that c-AMP-dependent protein phosphorylation maintains the spontaneous activity of calcium channels responsible for cytosolic calcium pulsing but does not mediate the channel-closing effects of dopamine and other secretoinhibitory neurotransmitters. Ann NY Acad Sci 680: 606-608.
108. Shibuya I, Douglas WW. 1993b. Spontaneous cytosolic calcium pulsing detected in Xenopus melanotrophs: modulation by secretagogues and stimulant ligands. Endocrinology 132:2166-2175.
109. Shibuya I, Douglas WW. 1993c. Spontaneous cytosolic calcium pulses in Xenopus melanotrophs are due to calcium influx during phasic increases in the calcium permeability of the cell membrane. Endocrinology 132:2176-2185.
110. Terlou M, Ploemacher RE. 1973. The distribution of monoamines in tel-, di-, and mesencephalon of Xenopus laevis tadpoles, with special reference to the hypothalamo-hypophysial system. Z Zellforsch 137: 521-540.
111. Terlou M, van Straaten HWM. 1973. The development of a hypothalamic monoaminergic system for the reguation of the pars intermedia activity in amphibians. Z Zellforsch 143:229-238.
112. Terlou M, Goos HJTh, van Oordt PGWJ. 1973. Hypothalamic regulation of pars intermedia activity in amphibians. Fortschr Zool 22: 117-133.
113. Tonon MC, Leroux P, Stoeckel ME, Jegou S, Pelletier G, Vaudry H. 1983. Catecholaminergic control of alpha-melanocyte-stimulating hormone (αMSH) release by frog neurointermediate lobe in vitro: evidence for direct stimulation of αMSH release by thyrotropin-releasing hormone. Endocrinology 112:133-141.
114. Tonon MC, Burlet A, Lauber M, Cuet P, Jégou S, Gouteaux L, Ling N, Vaudry H. 1985. Immunohistochemical localization and radioimmunoassay of corticotropin-releasing factor in the forebrain and hypophysis of the frog Rana ridibunda. Neuroendocrinology 40: 109-119.
115. Tonon MC, Bosler O, Stoeckel ME, Pelletier G, Tappaz M, Vaudry H. 1992. Co-localization of tyrosine hydroxylase, GABA and neuropeptide Y within axon terminals innervating the intermediate lobe of the frog Rana ridibunda. J Comp Neurol 319:599-605.
116. Tonosaki Y, Cruijsen PMJM, Nishiyama K, Yaginuma H, Roubos EW. 2001. Regulation of α-MSH release from the pituitary pars intermedia of Xenopus laevis in a cold environment. In: Goos HJTh, Rastogi RK, Vaudry H, Pierantoni R, editors. Perspective in comparative endocrinology: unity and diversity. Bologna: Monduzzi Editore. p 821-826.
117. Tuinhof R. 1995. Central regulation of melanotrope cells of Xenopus laevis. PhD thesis. University of Nijmegen.
118. Tuinhof R, Laurent FYSC, Ebbers RGE, Smeets WJAJ, van Kiel MCHM, Roubos EW. 1993. Immunocytochemistry and in situ hybridization of neuropeptide Y in the hypothalamus of Xenopus laevis in relation to background adaptation. Neuroscience 55:667-675.
119. Tuinhof R, Artero C, Fasolo A, Franzoni MF, Donkelaar HJ ten, Wismans PGP, Roubos EW. 1994a. Retinohypothalamic input, suprachiasmatic nucleus and locus coeruleus are involved in the neural control of the pars intermedia of the pituitary gland of Xenopus laevis. A retrograde and anterograde tracing study. Neuroscience 61:411-420.
120. Tuinhof R, González A, Smeets WJAJ, Roubos EW. 1994b. Neuropeptide Y in the developing and adult brain of the South African clawed toad Xenopus laevis. J Chem Neuroanat 7:271-283.
121. Tuinhof R, González A, Smeets WJAJ, Scheenen WJJM, Roubos EW. 1994c. Central control of melanotrope cells in Xenopus laevis. Eur J Morphol 32:307-310
122. Tuinhof R, Ubink R, Tanaka S, Atzori C, van Strien FJC, Roubos EW. 1998. Distribution of POMC and POMC-derived peptides in the adult brain of Xenopus laevis. Cell Tiss Res 292:251-265
123. Ubink R, Jenks BG, Roubos EW. 1997. Physiologically induced Fos expression in the hypothalamo-hypophyseal system of Xenopus laevis. Neuroendocrinology 65:413-422.
124. Ubink, R, Tuinhof R, Roubos EW. 1998. Identification of suprachiasmatic melanotrope-inhibiting neurones in Xenopus laevis: a confocal laser scanning microscopy study. J Comp Neurol 397:60-68.
125. Ubink R, Buzzi M, Cruijsen PMJM, Tuinhof R, Verhofstad AAJ, Jenks BG, Roubos EW. 1999. Serotonergic innervation of the pituitary pars intermedia of Xenopus laevis. J Neuroendocrinol 11:211-219.
126. van Strien FJC. 1996. Analysis of secretory signals from melanotrope cells of Xenopus laevis. Peptide characterization and regulation of release. PhD thesis. University of Nijmegen.
127. van Strien FJC, de Rijk EPCT, Heymen PSH, Hafmans TGM, Roubos EW. 1991. Demonstration of dopamine in electron-dense vesicles in the pars intermedia of Xenopus laevis, by freeze substitution and postembedding immunogold electron microscopy. Histochemistry 96:551-556.
128. van Strien FJC, Jenks BG, Heerma W, Versluis C, Kawauchi H, Roubos EW. 1993a. α-N-acetyl β-endorphin (1-8) is the terminal product of processing of endorphins in the melanotrope cells of Xenopus laevis as demonstrated by FAB tandem mass spectrometry. Biochem Biophys Res Commun 191:262-268.
129. van Strien FJC, Jenks BG, Roubos EW. 1993b. Evidence for independently regulated secretory pathways in the neurointermediate lobe of Xenopus laevis. Ann NY Acad Sci 680:639-642.
130. van Strien FJC, Devreese B, van Beumen J, Roubos, EW, Jenks BG. 1995a. Biosynthesis and processing of the N-terminal part of proopiomelanocortin in Xenopus laevis: characterization of α-MSH peptides. J Neuroendocrinol 7:807-815.
131. van Strien FJC, Galas L, Jenks BG, Roubos EW. 1995b. Differential acetylation of POMC-derived peptides in the pituitary gland of Xenopus laevis in relation to background adaptation. J Endocrinol 146:159-167.
132. van Strien FJC, Jespersen S, van der Greef J, Jenks BG, Roubos EW. 1996a. Identification of POMC processing products in single melanotrope cells by matrix-assisted laser desorption/ionization mass spectrometry. FEBS Lett 379:165-170.
133. van Strien FJC, Vaudry H, Roubos EW, Jenks BG. 1996b Acetylcholine autoexcites release of proopiomelanocortin-derived peptides from melanotrope cells of Xenopus laevis via a M1 muscarinic receptor. Endocrinology 137:4298-4307.
134. Vaudry H, Eberle AN, editors. 1993. The melanotropic peptides. Ann NY Acad Sci. Vol 680.
135. Vaudry H, Tonon MC, Roubos EW, De Loof A, editors. 1998. Trends in comparative endocrinology and neurobiology. From molecular to integrative biology. Ann NY Acad Sci. 750 pp.
136. Verburg-van Kemenade BML, Willems PHGM, Jenks BG, van Overbeeke AP. 1984. The development of the pars intermedia and its role in the regulation of dermal melanophores in the larvae of the amphibian Xenopus laevis. Gen Comp Endocrinol 55:54-65.
137. Verburg-van Kemenade BML, Jenks BG, Driessen AGJ. 1986a. GABA and dopamine act directly on melanotropes of Xenopus to inhibit αMSH-secretion. Brain Res Bull 17:697-704.
138. Verburg-van Kemenade BML, Jenks BG, van Overbeeke AB. 1986b. Regulation of melanotropin release from the pars intermedia of the amphibian Xenopus laevis: evaluation of the involvement of serotonergic, cholinergic, or adrenergic receptor mechanisms. Gen Comp Endocrinol 63:471-480.
139. Verburg-van Kemenade BML, Tappaz M, Paut L, Jenks BG. 1986c. GABA-ergic regulation of MSH secretion from the pars intermedia of Xenopus laevis: immunocytochemical and physiological evidence. Endocrinology 118:260-267.
140. Verburg-van Kemenade BML, Tonon MC, Jenks BG, Vaudry H. 1986d. Characteristics of receptors for dopamine in the pars intermedia of the amphibian Xenopus laevis. Neuroendocrinology 44: 446-456.
141. Verburg-van Kemenade BML, Jenks BG, Cruijsen PMJM, Dings A, Tonon M-C, Vaudry H. 1987a. Regulation of αMSH-release from the neurointermediate lobe of Xenopus laevis by CRF-like peptides. Peptides 8:1093-1100.
142. Verburg-van Kemenade BML, Jenks BG, Danger JM, Vaudry H. 1987b. A NPY-like peptide may function as MSH-inhibiting factor in Xenopus laevis. Peptides 8:61-68.
143. Verburg-van Kemenade BML, Jenks BG, Smits RJM. 1987c. N-Terminal acetylation of melanophore-stimulating hormone in the pars intermedia of Xenopus laevis is a physiologically regulated event. Neuroendocrinology 46:289-296.
144. Verburg-van Kemenade BML, Jenks BG, Visser TJ, Tonon M-C, Vaudry H. 1987d. Assessment of TRH as a potential αMSH-release stimulating factor in Xenopus laevis. Peptides 8:69-76.
145. Verhaert P, Marivoet S, Vandesande F. De Loof A. 1984. Localization of CRF immunoreactivity in the central nervous system of three vertebrate and one insect species. Cell Tiss Res 238:49-53.
146. Weatherhead B. 1983. The pars intermedia of the pituitary gland. In: Navaratnam V Harrison RJ , editors. Progress in anatomy. Cambridge University Press 3:1-32
147. Weatherhead B, Whur P. 1972. Quantification of ultrastructural changes in the 'melanocyte-stimulating hormone cell' of the pars intermedia of the pituitary of Xenopus laevis, produced by change of background colour. J Endocrinol 53:303-310.
148. Wilson JF, Morgan MA. 1979. α-Melanotropin-like substances in the pituitary and plasma of Xenopus laevis in relation to colour change responses. Gen Comp Endocrinol 38:172-182.
149. Zoeller RT, Conway KM. 1989. Neurones expressing thyrotropin-releasing hormone-like messenger ribonucleic acid are widely distributed in Xenopus laevis brain. Gen Comp Endocrinol 76:139-146.