title: Prolactin-thyroxine antagonism and the metamorphosis of visual pigments in Rana catesbeiana tadpoles.
abstract: The relationship between prolactin-thyroxin antagonism and the metamorphosis of visual pigments in larval amphibians has been investigated using bullfrog (Rana catesbeiana) tadpoles. Althought prolactin-thyroxine antagonism is demonstrable by morphological criteria, ovineprolactin does not appear to anatagonize thyroxine-induced rhodopsin synthesis. The hypothesisis offered that prolactin-thyroxine antagonism is the result of differential gene activities which are opposite in their physiological effects.
mesh_terms: D000818:Animals; D007274:Injections, Intraperitoneal; D007814:Larva; D008675:Metamorphosis, Biological; D011388:Prolactin / Q000008:administration & dosage / Q000494:pharmacology*; D011892:Rana catesbeiana; D012160:Retina / Q000032:analysis; D012168:Retinal Pigments / Q000096:biosynthesis*; D012243:Rhodopsin / Q000096:biosynthesis; D013623:Tail / Q000254:growth & development; D013974:Thyroxine / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D014801:Vitamin A / Q000032:analysis
chemical_list: D012168:Retinal Pigments; D014801:Vitamin A; D011388:Prolactin; D012243:Rhodopsin; D013974:Thyroxine