Plasma and testicular estradiol and plasma androgen profile in the male frog Rana esculenta during the annual cycle.
Seasonal plasma and testicular estradiol levels were measured in the male frogs, Rana esculenta, by radioimmunoassay. In plasma samples a simultaneous measurement of androgens was carried out in order to investigate a possible relationship between androgens and estradiol-17 beta. Concomitantly with the estradiol-17 beta peak in plasma and testes during the April-May period, plasma androgens sharply decreased.
D000728:Androgens / Q000097:blood; D000818:Animals; D004958:Estradiol / Q000097:blood / Q000378:metabolism*; D008297:Male; D011893:Rana esculenta / Q000502:physiology*; D012621:Seasons; D013737:Testis / Q000502:physiology
D000728:Androgens; D004958:Estradiol