Changes in the digestive tract and feeding behavior of anuran amphibians during metamorphosis

Physiological Zoology

Volumn 69, Issue 2, 1996, Pages 219-251

  Hourdry, Jacques ^a   L'Hermite, Alain ^b   Ferrand, Raymond ^b  

^a UNIVERSITÉ PARIS SACLAY   (France)

^b UNIVERSITÉ DE NANTES   (France)

Author keywords

[No Author keywords available]

Indexed keywords

DIGESTIVE TRACT; METAMORPHOSIS;

ANURA;

EID: 0029663457     PISSN: 0031935X     EISSN: None     Source Type: Journal    
DOI: 10.1086/physzool.69.2.30164181     Document Type: Review

References (133)

1. ALTIG, R., and G. F. JOHNSTON. 1989. Guilds of anuran larvae: relationship among developmental modes, morphologies and habitats. Herpetol. Monogr. 3:81-109.
2. ALTIG, R., J. P. KELLY, M. WELLS, and J. PHILLIPS. 1975. Digestive enzymes of seven species of anuran tadpoles. Herpetologica 31:104-108.
3. ANDÉOL, Y., J. HOURDRY, and M. MÉCHALI. 1992. Localization of ras proto-oncogene expression during development in Xenopus laevis. Mol. Reprod. Dev. 32:187-195.
4. ANDERSON, I. A., T. BRIGGS, G. A. D. HASLEWOOD, R. S. OLDHAM, H. SCHÄREN, and L. TOKÉS. 1979. Comparison of the bile salts of frogs with those of their tadpoles: bile salt changes during the metamorphosis of Rana catesbeiana Shaw. Biochem. J. 183:507-511.
5. ANDREW, A. 1974. Further evidence that enterochromaffin cells are not derived from the neural crest. J. Embryol. Exp. Morphol. 31:589-598.
6. ATKINSON, B. G., and G. H. LITTLE. 1972. Growth and regression in tadpole pancreas during spontaneous and thyroid hormone-induced metamorphosis. I. Rates of macromolecular synthesis and degradation. Mech. Ageing Dev. 1:299-312.
7. BALDWIN, G. F., and P. J. BENTLEY. 1980. Calcium metabolism in bullfrog tadpoles (Rana catesbeiana). J. Exp. Biol. 88:357-365.
8. BALOGUN, R. A., and O. FISHER. 1970. Studies on the digestive enzymes of the common African toad Bufo regularis Boulenger. Comp. Biochem. Physiol. 33B:813-820.
9. BARRINGTON, E. J. W. 1946. The delayed development of the stomach in the frog (Rana temporaria) and the toad (Bufo bufo). Proc. Zool. Soc. Lond. 116:1-21.
10. BEAUMONT, A. 1977. La dégénérescence partielle du pancréas larvaire des Amphibiens Anoures au cours de la métamorphose. Pages 113-124 in A. RAYNAUD, ed. Mécanismes de la rudimentation des organes chez les embryons de Vertébrés. CNRS, Paris.
11. BEAUMONT, A., J. HOURDRY, J. M. VERNIER, and M. WEGNEZ. 1994. Biologie des Vertébrés: développement. Dunod, Paris. 282 pp.
12. BEN BRAHIM, O., J. MESNARD, and J. HOURDRY. 1987. Hormonal control of the intestinal brush border enzyme activities in developing anuran amphibians. II. Effects of glucocorticoids and insulin during experimental metamorphosis. Gen. Comp. Endocrinol. 65:489-495.
13. BLOMQVIST, A., C. SODERBERG, I. LUNDELL, R. MILNER, and D. LARHAMMAR. 1992. Strong evolutionary conservation of neuropeptide Y: sequences of chicken, goldfish and Torpedo marmorata DNA clones. Proc. Natl. Acad. Sci. USA 89:2350-2354.
14. BONNEVILLE, M. 1963. Fine structural changes in the intestinal epithelium of the bullfrog during metamorphosis. J. Cell Biol. 18:579-597.
15. BROWN, A. C., and P. F. MILLINGTON. 1968. Electron microscope studies of phosphatases in the small intestine of Rana temporaria during larval development and metamorphosis. Histochemie 12:83-94.
16. BUCHAM, A. M. J. 1986. An immunocytochemical study of regulatory peptides in the amphibian gastrointestinal tract. Can. J. Zool. 64:1-7.
17. BURGGREN, W. W., and J. J. JUST. 1992. Developmental changes in physiological systems. Pages 467-530 in M. E. FEDER and W. W. BURGGREN, eds. Environmental physiology of the Amphibians. University of Chicago Press, Chicago.
18. CHENG-KAUNG, H. L. 1983a. Immunocytochemical localization of pancreatic endocrine cells in frog embryos and young larvae. Gen. Comp. Endocrinol. 45:204-211.
19. _. 1983b. Changes of pancreatic beta cell population during larval development of Rana pipiens. Gen. Comp. Endocrinol. 49:50-56.
20. CRUMP, M. L. 1986. Cannibalism by younger tadpoles: another hazard of metamorphosis. Copeia 1986:1007-1009.
21. DAUÇA, M., R. CALVERT, D. MÉNARD, J. S. HUGON, and J. HOURDRY. 1982. Development of peroxisomes in amphibians. I. Cytochemical and biochemical studies on the small intestine. J. Exp. Zool. 200:235-241.
22. DAUÇA, M., and J. HOURDRY. 1978. Analyse quantitative des remaniements intestinaux et évolution de la synthèse de l'ADN: étude chez les larves d'Alytes obstetricans et de Discoglossus pictus (Amphibiens Anoures) en métamorphose spontanée. Biol. Cell 31:277-286.
23. DAUÇA, M., J. HOURDRY, J. S. HUGON, and D. MÉNARD. 1979. Amphibian intestinal brush border membranes. I. Isolation from Rana catesbeiana tadpole. Comp. Biochem. Physiol. 64B:155-159.
24. _. 1980. Amphibian intestinal brush border membranes. II. Isolation from Rana catesbeiana adult. Comp. Biochem. Physiol. 666:111-115.
25. _. 1981. Amphibian intestinal brush border membranes. III. Comparison during metamorphosis of the protein, glycoprotein and enzyme patterns after gel electrophoretic separation of SDS solubilized membranes. Comp. Biochem. Physiol. 69B:15-22.
26. DE DUVE, C., and R. WATTIAUX. 1966. Functions of lysosomes. Annu. Rev. Physiol. 28:392-425.
27. DE JONGH, H. J. 1968. Functional morphology of the jaw apparatus of larval and metamorphosing Rana temporaria L. Neth. J. Zool. 18:1-103.
28. DEL PINO, E. M. 1989. Marsupial frogs. Sci. Am. 260:110-118.
29. DEL PINO, E. M., and B. ESCOBAR. 1981. Embryonic stages of Gastrotheca riobambae (Fowler) during maternal incubation and comparison of development with that of other egg-brooding hylid frogs. J. Morphol. 167:277-295.
30. DUELLMAN, W. E., and L. TRUEB. 1986. Biology of amphibians. McGraw-Hill, New York. 670 pp.
31. EL MARAGHI-ATER, H., J. MESNARD, and J. HOURDRY. 1986. Hormonal control of intestinal brush border enzyme activities in developing anuran amphibians. I. Effects of hydrocortisone and insulin during and after spontaneous metamorphosis. Gen. Comp. Endocrinol. 61:53-63.
32. FALKMER, S., R. P. ELDE, C. HELLERSTROM, S. EFFENDIC, J. FOLHMAN, and J. B. SILJEVALL. 1977. Some phylogenetical aspects of the occurrence of somatostatin in the gastroenteropancreatic system. Arch. Histol. Jpn. 40:99-118.
33. FALKMER, S., M. EL-SAHLY, and M. TILTACH. 1984. Evolution of the neuroendocrine system in vertebrates: a review with particular reference to the phylogeny and postnatal maturation of the islet parenchyma. Pages 59-87 in S. FALKMER, R. HAKANSON, and F. SUNDLER, eds. Evolution and tumour pathology of the neuroendocrine system. Elsevier, Amsterdam.
34. FIGIEL, A., and M. DAUÇA. 1990. Influence of triiodothyronine on the polypeptide composition of the intestinal brush border membrane during amphibian metamorphosis. Int. J. Dev. Biol. 34:399-407.
35. FIGIEL, A., J. SCHILT, B. DUDOUET, S. ROBINE, and M. DAUÇA. 1987. Stage-specific polypeptides and villin expression during the intestinal epithelium substitution of the metamorphosing amphibian. Differentiation 36:116-124.
36. FORTE, J. G. E., L. LIMLOMWONGSE, and D. K. KASBEKAR. 1969. Ion transport and the development of hydrogen ion secretion in the stomach of the metamorphosing bullfrog tadpole. J. Gen. Physiol. 54:76-95.
37. FOX, H. 1984. Amphibian morphogenesis. Humana, Clifton, N.J. 301 pp.
38. FRIEDEN, E., J. DRAKE, and A. KISTLER. 1981. Effects of protein synthesis inhibitors on A- and L-site amino acid incorporation by bullfrog tadpole liver and tail fin cells. Int. J. Biochem. 13:281-286.
39. FRIEDEN, E., and J. J. JUST. 1970. Hormonal responses in amphibian metamorphosis. Pages 1-52 in G. LITWAK, ed. Biochemical actions of hormones. Vol. 1. Academic Press, New York.
40. FURNESS, J. B., J. W. HEATH, and M. COSTA. 1978. Aqueous aldehyde (Fuglu) methods for the fluorescence histochemical localization of catecholamines and ultrastructural studies of central nervous tissues. Histochemistry 57:4-14.
41. GARRIDO, O., E. PUGIN, and B. JORQUERA. 1975. Correspondance ultrastructurale entre la bourse gutturale du Rhinoderma darwini et le tégument des larves. Boll. Zool. 42:133-144.
42. GARVEY, T. Q., P. E. HYMAN, and K. J. ISSELBACHER. 1976. γ-Glutamyltranspeptidase of rat intestine: localization and possible role in amino acid transport. Gastroenterology 21:778-785.
43. GAZE, R. M., M. J. KEATING, and S. H. CHUNG. 1974. The evolution of the retinotectal map during development in Xenopus. Proc. R. Soc. Lond. Biol. 185:301-330.
44. GILBERT, L. I., and E. FRIEDEN. 1981. Metamorphosis: a problem in developmental biology. Plenum, New York. 578 pp.
45. GRADWELL, N. 1972. Gill irrigation in Rana catesbeiana. Can. J. Zool. 50:481-521.
46. GRIFFITHS, I. 1961. The form and function of the fore-gut in anuran larvae (Amphibia, Salienta) with particular reference to the manicotto glandulare. Proc. Zool. Soc. Lond. 137:249-283.
47. HANKEN, J. 1993. Model systems versus outgroups: alternative approaches to the study of head development and evolution. Am. Zool. 33:448-456.
48. HELANDER, H. F. 1981. The cells of the gastric mucosa. Int. Rev. Cytol. 70:217-289.
49. HEUSSER, S., S. COLIN, A. FIGIEL, C. HUET, J. M. KELLER, P. PORNET, S. ROBINE, J. VANDAMME, J. VANDEKERCKOVE, and M. DAUÇA. 1992. Amphibian intestinal villin: isolation and expression during embryonic and larval development. J. Cell Sci. 103:699-708.
50. HITTLER, K., J. PABST, and W. HANKE. 1978. Hormonal influences on the release of free fatty acids into the blood in different metamorphic stages in Xenopus. Gen. Comp. Endocrinol. 34:96.
51. HOURDRY, J. 1973. Remaniements de l'epithelium intestinal chez les Amphibiens Anoures en métamorphose. L'Année Biol. 12:97-138.
52. HOURDRY, J., and A. BEAUMONT. 1985. Les métamorphoses des Amphibiens. Masson/ Singer-Polignac, Paris. 275 pp.
53. HOURDRY, J., A. BRULFERT, M. GUSSE, D. SCHOEVAERT, M. V. TAYLOR, and M. MÉCHALI. 1988. Localization of c-myc expression during oogenesis and embryonic development in Xenopus laevis. Development 104:631-641.
54. HOURDRY, J., J. G. CHABOT, D. MÉNARD, and J. S. HUGON. 1979. Intestinal brush border enzyme activities in developing amphibian Rana catesbeiana. Comp. Biochem. Physiol. 63A:121-125.
55. HOURDRY, J., and M. DAUÇA. 1977. Cytological and cytochemical changes in the intestinal epithelium during anuran metamorphosis. Int. Rev. Cytol. Suppl. 5:337-385.
56. HOURDRY, J., J. M. GUINET, Y. ANDÉOL, and M. MÉCHALI. 1991. Expression des protooncogènes au cours du développement des Amphibiens. In Table Ronde: apports de la biologie moléculaire à la compréhension de la morphogenèse. Bull. Soc. Zool. Fr. 116:159-169.
57. HOURDRY, J., and J. S. HUGON. 1979. Ultrastructural localization of alkaline phosphatase activity in the intestine of developing Rana catesbeiana. Histochemistry 63:181-190.
58. HOURDRY, J., and M. TRUCHET. 1976. Aluminium localization in amphibian epidermis with the electron microprobe (EMP) and ion microanalyzer (IMA). Tissue Cell 8:175-181.
59. HULSEBUS, J., and E. S. FARRAR. 1985. Insulin-like immunoreactivity in serum and pancreas of metamorphosing tadpoles. Gen. Comp. Endocrinol. 58:114-119.
60. INOKUCHI, T., K. I. KOBAYASHI, and S. HORIUCHI. 1991. Acid proteinases of the foregut in metamorphosing tadpoles of Rana catesbeiana. Comp. Biochem. Physiol. 99B:653-662.
61. ISHIZUYA-OKA, A., and A. SHIMOZAWA. 1987. Ultrastructural changes in the intestinal connective tissue of Xenopus laevis during metamorphosis. J. Morphol. 193:13-22.
62. _. 1990. Changes in lectin-binding pattern in the digestive tract of Xenopus laevis during metamorphosis. II. Small intestine. J. Morphol. 205:9-15.
63. JAFFE, R. C. 1981. Plasma concentration of corticosterone during Rana catesbeiana tadpole metamorphosis. Gen. Comp. Endocrinol. 44:314-318.
64. KALTENBACH, J. C., M. J. LIPSON, and C. H. K. WANG. 1977. Histochemical study of the amphibian digestive tract during normal and thyroxine-induced metamorphosis. I. Alkaline phosphatase. J. Exp. Zool. 202:103-120.
65. KATZ, L. C., M. J. POTEL, and R. J. WASSERSUG. 1981. Structure and mechanisms of schooling in tadpoles of the clawed frog, Xenopus laevis. Anim. Behav. 29:20-33.
66. KENNY, J. S. 1969. Feeding mechanisms in anuran larvae. J. Zool. Lond. 157:225-246.
67. KERR, J. F. R., A. H. WYLLIE, and A. R. CURRIE. 1972. Apoptosis: a basic biological phenomenon with wide-ranging implications in tissue kinetics. Br. J. Cancer 26: 239-257.
68. KIKUYAMA, S., K. NIKI, M. MAYUMI, and K. KAWAMURA. 1983. Retardation of thyroxine-induced metamorphosis by amphenone B in toad tadpoles. Endocrinol. Jpn. 29: 659-662.
69. KISTLER, A., H. MIYAUCHI, and E. FRIEDEN. 1980. Changes in amino acid metabolism and protein synthesis during spontaneous metamorphosis in the bullfrog tadpole liver. Int. J. Biochem. 12:395-400.
70. KRUG, E. C., K. V. HONN, J. BATTISTA, and C. S. NICOLL. 1983. Corticosteroids in serum of Rana catesbeiana during development and metamorphosis. Gen. Comp. Endocrinol. 52:232-241.
71. KUJAT, R. 1981. Pepsin and trypsin activity in the fore-gut of metamorphosing Xenopus laevis larvae. Folia Biol. (Krakow) 29:275-278.
72. KUJAT, R., and B. DROBA. 1979. Acid proteolytic activity in the fore-gut of the Xenopus laevis larvae. Comp. Biochem. Physiol. 63A:543-545.
73. LAMBERTINI, G. 1928. Il manicotto glandulare di Rana esculenta. Ricerche Morfol. (Roma) 9:71-88.
74. LANNOO, M. J., D. S. TOWNSEND, and R. J. WASSERSUG. 1987. Larval life in the leaves: arboreal tadpole types, with special attention to the morphology, ecology, and behavior of the oophagous Osteopilus brunneus (Hylidae) larvae. Fieldiana: Zool. 38:1-31.
75. LARSEN, L. O. 1984. Feeding in adult toads: physiology, behaviour, ecology. Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening 145:97-116.
76. LELOUP, J., and M. BUSCAGLIA. 1977. La triiodothyronine, hormone de la métamorphose des Amphibiens. C. R. Acad. Sci. III 284:2261-2263.
77. LEONE, F., S. LAMBERT-GARDINI, C. SARTORI, and S. SCAPIN. 1976. Ultrastructural analysis of some functional aspects of Xenopus laevis pancreas during development and metamorphosis. J. Embryol. Exp. Morphol. 36:711-724.
78. L'HERMITE, A., R. FERRAND, M. P. DUBOIS, and A. C. ANDERSEN. 1985. Detection of endocrine cells by immunofluorescence method in the gastroenteropancreatic system of the adult eel, glass-eel and leptocephalic larva (Anguilla anguilla L.). Gen. Comp. Endocrinol. 58:347-357.
79. L'HERMITE, A., J. HOURDRY, and R. FERRAND. 1988. Investigations of endocrine cells in the gastrointestinal tract and pancreas during the metamorphosis of an anuran (Alytes obstetricans L.): histochemical detection of APUD cells. Gen. Comp. Endocrinol. 69:381-390.
80. MAEKAWA, H., and K. YAMANA. 1975. Alkaline phosphatase isozymes of Xenopus laevis embryos and tissues. J. Exp. Zool. 192:155-164.
81. MANFREDI-ROMANINI, M. G., and A. FRASCHINI. 1965. Sulla differenziazione funzionale della mucosa esofagea e gastrica di Rana esculenta (con particolare riguardo al significativo attribuibile al "manicotto ghiandolare" di Ruffini). Boll. Zool. 32: 459-473.
82. MCAVOY, J. W., and K. E. DIXON. 1977. Cell proliferation and renewal in the small intestinal epithelium of metamorphosing and adult Xenopus laevis. J. Exp. Zool. 202:129-138.
83. _. 1978. Cell specialization in the small intestinal epithelium of adult Xenopus laevis: functional aspects. J. Anat. 125:237-245.
84. MEISTER, A. 1973. On the enzymology of amino acid transport. Science 180:33-39.
85. MONSTEIN, H., J. THORUP, R. FOLKESSON, A. JOHNSEN, and J. REHFELD. 1993. cDNA deduced procionin: structure and expression in protochordates resemble that of procholecystokinin in mammals. FEBS Lett. 331:60-64.
86. NAGALLA, S. R., B. W. GIBSON, D. TANG, J. R. REEVE, and E. R. SPINDEL. 1992. Gastrin-releasing peptide (GRP) is not mammalian bombesin: identification and molecular cloning of a true amphibian GRP distinct from amphibian bombesin in Bombina orientalis. J. Biol. Chem. 267:6916-6922.
87. NAITOH, T., R. J. WASSERSUG, and R. A. LESLIE. 1989. The physiology, morphology, and ontogeny of emetic behavior in anuran amphibians. Physiol. Zool. 62:819-843.
88. NISHIKAWA, K. C., and G. ROTH. 1991. The mechanism of tongue protraction during prey capture in the frog Discoglossus pictus. J. Exp. Biol. 159:217-234.
89. OHTAKE, S. I. 1982. Gastric differentiation of anuran larvae. Bull. Liberal Arts Sci. Course Nihon Univ. Sch. Med. 10:1-14.
90. OINUMA, T., J. I. KAWANO, and T. SUGANUMA. 1991. Glycoconjugate histochemistry of Xenopus laevis fundic gland with special reference to mucous neck cells during development. Anat. Rec. 230:502-512.
91. _. 1992. Bromodeoxyuridine-immunohistochemistry on cellular differentiation and migration in the fundic gland of Xenopus laevis during development. Cell Tissue Res. 269:205-212.
92. PEARSE, A. G. E. 1969. The cytochemistry and ultrastructure of polypeptide hormone-producing cells of the APUD series and the embryologic, physiologic and pathologic implication of the concept. J. Histochem. Cytochem. 17:303-313.
93. PIAVAUX, A. 1972. β-Polysaccharidases du tube digestif de Rana temporaria L. pendant la croissance et la métamorphose. Arch. Int. Physiol. Biochim. 80:153-160.
94. POLIS, G. A., and C. A. MYERS. 1985. A survey of intraspecific predation among reptiles and amphibians. J. Herpetol. 19:99-107.
95. POUYET, J. C., and J. HOURDRY. 1988. In vitro study of the intestinal brush border enzyme activities in developing anuran amphibian: effects of thyroxine, cortisol and insulin. J. Exp. Zool. 245:200-205.
96. POUYET, J. C., J. MESNARD, and J. HOURDRY. 1983. Modifications histologiques et dynamiques provoquées par la thyroxine sur la région gastrique de la larve du Discoglosse (Amphibien Anoure). Bull. Soc. Zool. Fr. 108:37-46.
97. REEDER, W. G. 1964. The digestive system. Pages 99-149 in J. A. MOORE, ed. Physiology of the Amphibia. Academic Press, New York.
98. REINECKE, M., C. MAAKE, S. FALKMER, and V. SARA. 1993. The branching of insulin-like growth factor I and insulin: an immunohistochemical analysis during phylogeny. Regul. Pept. 48:65-76.
99. ROMBOUT, J. H. W. M. , C. J. J. LAMERS, and J. G. HANSTEDE. 1978. Enteroendocrine APUD cells in the digestive tract of larval Barbus conchonius (Teleostei, Cyprinidae). J. Embryol. Exp. Morphol. 47:121-135.
100. RUIBAL, R., and E. THOMAS. 1988. The obligate carnivorous larvae of the frog, Lepidobatrachus laevis(Leptodactylidae). Copeia 1988:591-604.
101. RUIZ, M. C., A. ACOSTA, M. J. ABAD, and F. MICHELANGELI. 1993. Non-parallel secretion of pepsinogen and acid by gastric oxyntopeptic cells of the toad (Bufo marinus). Am. J. Physiol. 265:G934-G941.
102. SAIDANE, D., G. BOGE, B. TRITAR, and G. PERES. 1991. Glycin transport by intestinal brush border vesicles of the amphibian Discoglossus pictus. Comp. Biochem. Physiol. 100A:931-935.
103. SAVAGE, R. M. 1952. Ecological, physiological and anatomical observations of some species of anuran tadpoles. Proc. Zool. Soc. Lond. 122:467-514.
104. SAWANT, V. A., and A. T. VARUTE. 1973. Lipid changes in the tadpoles of Rana tigrina during growth and metamorphosis. Comp. Biochem. Physiol. 44B:729-750.
105. SCAPIN, S., and S. LAMBERT-GARDINI. 1979. Digestive enzymes in the exocrine pancreas of the frog Rana esculenta. Comp. Biochem. Physiol. 62A:691-697.
106. SEALE, D. B. 1987. Amphibia. Pages 467-552 in P. J. VERNBERG and T. J. PANDIAN, eds. Vol. 2. Animal energetics. Academic Press, New York.
107. SHI, Y. B., and D. D. BROWN. 1990. Developmental and thyroid hormone-dependent regulation of pancreatic genes in Xenopus laevis. Genes Dev. 4:1107-1113.
108. _. 1993. The earliest changes in gene expression in tadpole intestine induced by thyroid hormone. J. Biol. Chem. 268:20312-20317.
109. SHI, Y. B., and W. P. HAYES. 1994. Thyroid hormone-dependent regulation of the intestinal fatty acid-binding protein gene during amphibian metamorphosis. Dev. Biol. 161:48-58.
110. SMIT, H. 1968. Gastric secretion in the lower vertebrates and birds. Pages 2791-2805 in C. F. CODE, ed. Handbook of physiology. Vol. 5. Alimentary canal. Sec. 6. Bile, digestion, ruminal physiology. Bethesda, Md., American Physiological Society.
111. SOKOL, O. M. 1969. Feeding in the pipid frog Hymenochirus boettgeri (Tornier). Herpetologica 25:9-24.
112. _. 1977. The free-swimming Pipa larvae, with a review of pipid larvae and pipid phylogeny (Anura: Pipidae). J. Morphol. 154:357-426.
113. SPIEGEL, E. S., and M. SPIEGEL. 1970. Some observations on the ultrastructure of the hepatocyte in the metamorphosing tadpole. Exp. Cell Res. 61:103-112.
114. SUGIMOTO, K., Y. ICHIKAWA, and I. NAKAMURA. 1981. Absorption of protein molecules by the small intestine of the bullfrog tadpole, Rana catesbeiana. J. Exp. Zool. 215:53-62.
115. TAYLOR, A. C., and J. J. KOLLROS. 1946. Stages in the normal development of Rana pipiens larvae. Anat. Rec. 94:7-23.
116. TAYLOR, P. M., and M. J. TYLER. 1986. Pepsin in the toad Bufo marinus. Comp. Biochem. Physiol. 84A:669-672.
117. TOLOZA, E. M., and J. M. DIAMOND. 1990. Ontogenetic development of nutrient transporters in bullfrog intestine. Am. J. Physiol. 258:G760-G769.
118. TYLER, M. J. 1991. Declining amphibian populations, a global phenomenon? an Australian perspective. Alytes 9:43-50.
119. TYLER, M. J., D. J. C. SHEARMAN, R. FRANCO, P. O'BRIEN, R. F. SEAMARK, and R. KELLY. 1983. Inhibition of gastric acid secretion in the gastric brooding frog Rheobatrachus silus. Science 220:609-610.
120. UEK, M. 1967. Der Manicotto glandulare ("Drüsenmagen") der Anurenlarve in Bau, Funktion und Beziehung zur Gesamtlänge des Darmes: eine mikroskopisch-anatomische, histochemische, und elektronenoptische Studie an der omnivoren und mikrophagen Larve von Xenopus laevis und der carnivoren und makrophagen Larve von Hymenochirus boettgeri (Anura, Pipidae). Z. Wiss. Zool. 176:173-270.
121. VAN NOORDEN, S., J. GREENBERG, and A. G. E. PEARSE. 1972. Cytochemical and immunofluorescence investigations on polypeptide hormone localization in the pancreas and gut of the larval lamprey. Gen. Comp. Endocrinol. 19:192-199.
122. WAKE, M. H. 1982. Diversity within a framework of constraints: amphibian reproductive modes. Pages 87-106 in D. MOSSAKOWSKI and G. ROTH, eds. Environmental adaptation and evolution. Fischer, Stuttgart.
123. WARD, P. H., V. K. NEUMANN, and L. CHIANG. 1978. Partial characterization of pepsins and gastricsins and their zymogens from human and toad gastric mucosae. Comp. Biochem. Physiol. 61B:491-498.
124. WASSERSUG, R. J. 1975. The adaptative significance of the tadpole stage with comments on the maintenance of complex life cycles in anurans. Am. Zool. 15:405-417.
125. _. 1989. Locomotion in amphibian larvae (or "why aren't tadpoles built like fishes?"). Am. Zool. 29:65-84.
126. WASSERSUG, R. J., and K. HOFF. 1979. A comparative study of the buccal pumping mechanism of tadpoles. Biol. J. Linnean Soc. 12:225-259.
127. WASSERSUG, R., and K. ROSENBERG. 1979. Surface anatomy of branchial food traps of tadpoles: a comparative study. J. Morphol. 159:393-426.
128. WILBUR, H. M. and J. P. COLLINS. 1973. Ecological aspects of amphibian metamorphosis: nonnormal distributions of competitive ability reflect selection for facultative metamorphosis. Science 182:1305-1314.
129. XAVIER, F. 1973. Le cycle des voies génitales femelles de Nectophrynoides occidentalis Angel, amphibien anoure vivipare. Z. Zellforsch. 140:509-534.
130. YAKABE, E., M. TANJI, M. ICHINOSE, S. GOTO, K. MIKI, K. KUROKAWA, H. ITO, T. KAKEYAMA, and K. TAKAHASHI. 1991. Purification, characterization, and amino acid sequences of pepsinogens and pepsins from the esophageal mucosa of bullfrog (Rana catesbeiana). J. Biol. Chem. 266:22436-22443.
131. YAOITA, Y., and D. D. BROWN. 1990. A correlation of thyroid hormone receptor gene expression with amphibian metamorphosis. Genes Dev. 4:1917-1924.
132. YAOITA, Y., Y. B. SHI, and D. D. BROWN. 1990. Xenopus laevis α- and β-thyroid hormone receptors. Proc. Natl. Acad. Sci. USA 87:7090-7094.
133. ZIPSER, R. D., P. LIGHT, and H. A. BERN. 1969. Comparative effects of mammalian prolactin and growth hormone on growth in the toads Bufo boreas and Bufo marinus. Gen. Comp. Endocrinol. 13:382-391.