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

Science  11 Feb 1972:
Vol. 175, Issue 4022, pp. 637-638
DOI: 10.1126/science.175.4022.637


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.