Measurement of plasma and hypothalamic luteinizing hormon-releasing hormone in pregnant mare serum-induced ovulating immature rats.
A radioimmunoassay for luteinizing hormone-releasing hormone (LH-RH) is described which is capable of detecting LH-RH in plasma and brain tissues. Fluctuations in plasma and hypothalamic LH-RH as well as plasma LH were measured in immature female rats in which ovulation was induced by a single injection of pregnant mare serum (PMS). High plasma levels of LH-RH were found 47-49 h after the initial injection of PMS, coincident with high plasma LH concentrations. However plasma LH-RH levels were considerably lower at 55-57 h post-PMS, when plasma LH levels were elevated. Hypothalamic LH-RH content could not be correlated with either plasma LH-RH or LH levels.
D000818:Animals; D000937:Antigen-Antibody Reactions; D002850:Chromatography, Gel; D004305:Dose-Response Relationship, Drug; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000097:blood / Q000378:metabolism*; D006064:Gonadotropins, Equine / Q000494:pharmacology*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D010060:Ovulation / Q000187:drug effects*; D011817:Rabbits / Q000276:immunology; D051381:Rats; D013997:Time Factors
D006064:Gonadotropins, Equine; D007987:Gonadotropin-Releasing Hormone