Sex-related difference in the rat pituitary [Met5]-enkephalin level--altered by gonadectomy.
Ontogenetic study of the rat pituitary [Met5]-enkephalin-like immunoreactivity (ME-LI) revealed that a sex-related difference in the level of this peptide began at 35 days of age. By 70 days of age, the level of male ME-LI was twice that of the female. Castration reduced the ME-LI in male rats and increased the ME-LI in female rats. These results suggest a possible role of sex hormones in regulating the pituitary enkephalin system.
D000375:Aging; D000818:Animals; D002369:Castration; D004744:Enkephalin, Methionine / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D008297:Male; D010902:Pituitary Gland / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D012737:Sex Factors; D012741:Sexual Maturation
D004958:Estradiol; D004744:Enkephalin, Methionine