Influence of starvation on the dihydrotestosterone-luteinizing hormone feedback in the male rat.
The suppressing effect of dihydrotestosterone (DHT) on LH secretion in freshly castrated starved and control rats was studied by implanting DHT releasing silastic capsules of various sizes. Lower plasma levels of DHT are needed to suppress the castration induced LH increase in the starved animals. Intravenous injection of tritiated testosterone (18 muCi/100 g b.wt) revealed a significantly longer half-life (12.4 vs 8.9; P less than 0.05) in the starved rat. The ratio [3H]-DHT/[3H]-T in plasma at various times after injection was not significantly different in starved and control animals. The results indicate that the increased sensitivity of the T-LH feedback report earlier [1] cannot be explained by a greater conversion T-DHT in the starved male rat.
D000818:Animals; D002369:Castration; D013196:Dihydrotestosterone / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D004343:Drug Implants; D005246:Feedback; D006207:Half-Life; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013217:Starvation / Q000378:metabolism*; D013739:Testosterone / Q000378:metabolism
D004343:Drug Implants; D013196:Dihydrotestosterone; D013739:Testosterone; D007986:Luteinizing Hormone