Abstract
Montclair State College, Department of Biology, Upper Montclair, New Jersey 07043, and *New Jersey Medical School, Newark, New Jersey 07103, U.S.A. (Received 15 September 1975) In recent years, there have been reports of an antagonistic effect between prolactin and thyroxine in amphibians (Bern, Nicoll & Strohman, 1967; Etkin & Gona, 1967; Gona, 1967) as well as in mammals (Mittra, 1974). In the red-spotted newt, Notophthalmus (Triturus) viridescens, we have been able to obtain the antagonistic effect described by Grant & Cooper (1965) with relatively large doses of thyroxine (Gona, Pearlman & Etkin, 1970). However, in hypophysectomized and thyroidectomized red efts (terrestrial stage of the red-spotted newt), the second metamorphosis-inducing effect of prolactin was greatly facilitated by 0·01 ng thyroxine/g body weight (Gona, Pearlman & Gona, 1973). In view of the report that the effect of prolactin on the mammary gland is most pronounced in the absence of thyroid hormone (Mittra,
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
