The modification by temperature of the effects of mammalian follicle stimulating hormone and 17B-estradiol on the process of vitellogenesis in the lizard, Anolis carolinensis
Date of Award
Master of Science
The effects of porcine follicle stimulating hormone, 17B-estradiol, and a combination of the two on the process of vitellogenesis were studied in Anolis carolinensis maintained at 15C with no light for one week, and then at 15C or 32C with 14 hours of light for two additional weeks.
At both temperatures, the control animals subjected to 14 hours of light possessed greater numbers of previtellogenic follicles and lower liver weights than the control animals sacrificed after one week in the dark. Animals maintained at the higher temperature and given different hormonal treatments showed significant increases in ovary and oviduct weights, the number of vitellogenic follicles, the diameters of the largest previtellogenic and vitellogenic follicles, and the percentage of vitelloprotein.
Previous research has suggested that low temperatures inhibit vitellogenesis by inactivating ovarian enzymes in volved in estrogen svnthesis . The results of the present research suggest that the estrogen may be synthesized, but that it is unable to stimulate oviduct growth at 15C. The low temperature also inhibits the synthesis of vitelloprotein by the liver. It was also shown that the presence of folli cle stimulating hormone increases the uptake of vitelloprotein by the ovarian follicles.
Early, Susan Howard, "The modification by temperature of the effects of mammalian follicle stimulating hormone and 17B-estradiol on the process of vitellogenesis in the lizard, Anolis carolinensis" (1976). Master's Theses. 391.