Effects of mammalian and host gonadotropins on the ovaries and oviducts of female texas horned lizards, Phrynosoma cornutum

Abstract

1. 1. The effects of bovine luteinizing hormone (LH), ovine follicle-stimulating hormone (FSH), ovine prolactin, Phrynosoma pituitary extract and pituitary extract that had been treated with neuraminidase were studied on the reproductive system of female horned lizards. Animals were hypophysectomized, and hormone treatments were begun on the sixth day following surgery. 2. 2. In hypophysectomized control animals no significant changes in ovarian weights were noted from the intact controls; however, there was a significant decrease in the oviduct weights and the width of the oviduct wall. 3. 3. Treatment with mammalian LH (1 mg) and FSH (1 mg) produced significant increases in follicle wall diameters. In all cases the stimulation of FSH was greater than that of LH. Concurrent treatment with FSH and LH did not produce synergistic effects. 4. 4. Animals treated with prolactin (2·5 mg) exhibited no increase in ovarian weight but did show increases in oviduct weight, width of oviduct wall and width of follicle walls. Prolactin treatment also induced profuse ecdysis. 5. 5. Treatment with host pituitary extract (2·5 mg) produced significant increases in all parameters. On the other hand, neuraminidase treatment appeared to destroy completely the biological activity of the preparation. This suggests that the Phrynosoma gonadotropin molecule is “FSH-like”.