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Neural timing of ovulation in immature rats treated with gonadotrophin
Science (New York, N.Y.)
|September 14, 1962
Abstract:
Treated with Gonadotrophin Thirty-two-day-old female rats, injected two days previously with gonadotrophin from pregnant mares' serum, were given barbiturate at different times during the afternoon to determine whether the ovulation that would occur the next day could be blocked. The results indicate that ovulation depends upon release of pituitary ovulating hormone during a"critical period" between 2 and 4 P.M.
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01:22Hormonal Regulation of the Menstrual Cycle
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At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
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