title: Diurnal variation of follicle stimulating hormone (FSH) in the male rat.
abstract: The phenomenon of diurnal variation in secretion of FSH, LH and prolactin (Prl) has been investigated in adult male Wistar rats. When these animals were decapitated at 2 h intervals throughout the 24 h day, a highly significant elevation of serum FSH was observed at 12.30 and 14.30 h. No definite diurnal pattern was observed for LH and Prl. The basic FSH rhythm was found to persist in animals bled via an indwelling atrial cannula or by cardiac puncture. However, these techniques of blood collection were found to produce some variation in the timing of the surge. These observations suggest the existence of diurnal variation in the secretion of FSH in the adult male rat.
mesh_terms: D000818:Animals; D001800:Blood Specimen Collection / Q000379:methods; D002940:Circadian Rhythm; D005640:Follicle Stimulating Hormone / Q000097:blood*; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D011388:Prolactin / Q000097:blood; D051381:Rats / Q000097:blood*; D012737:Sex Factors
chemical_list: D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone