Ovulation in Hamster: Induction by β Subunit of Ovine Interstitial Cell Stimulating Hormone

• DOI: 10.1126/science.175.4022.637
• Publication Date: 2006-10-05T14:03:38Z
• Authors: W. H. Yang; M. R. Sairam; Harold Papkoff; Choh Hao Li
• Keywords: Ovulation; 0301 basic medicine; Time Factors; Luteinizing Hormone; Stimulation, Chemical; 3. Good health; 03 medical and health sciences; Estrus; Pregnancy; Cricetinae; Animals; Female; Injections, Intraperitoneal; Hypophysectomy

As little as 5 micrograms of interstitial cell stimulating hormone (ICSH) or 20 micrograms of ICSH-β is effective for the induction of ovulation in 100 percent of hamsters treated at 0500 hours on day 4 after lordosis, whereas as much as 800 micrograms of ICSH-α is ineffective. Both ICSH and ICSH-β are also effective for induction of ovulation in hypophysectomized animals. Thus, the ovulation-inducing activity of the ICSH molecule resides in its β subunit.