Heparin: a potent inhibitor of ovarian luteinizing hormone-sensitive adenylate cyclase.

Sulfated mucopolysaccharides, such as heparin, heparan sulfate, chondroitin sulfates and dermatan sulfate, have been shown to be normal constituents of animal tissues and body fluids. Their biological functions are not yet known with certainty. A role as lubricants in the living organism was ascribed to these sulfated mucopolysaccharides due to their highly viscous and elastic properties in solution. Heparin displays anticoagulant and anti-lipaemic properties [ 11. Direct effects on various enzymes have been described for polyelectrolytes including heparin and other sulfated glycosaminoglycans [2,3]. Wolff and Cook [4] have recently described the effects of polycations (RNAase A, spermin, spermidine and polylysine) and of polyanions (Dextran sulfate, Suramin and polyaspartic acid) on bovine thyroid-stimulatinghormone-sensitive adenylate cyclase. Hyaluronic acid and chondroitin sulfuric acid were shown to be constituents of the follicular fluid in the bovine ovary [5] . We have recently shown that heparinlike substances as well as chondroitin+ulfate, chondroitin-6-sulfate and dermatan sulfate are synthesized and accumulate in the rat ovary [6,7]. In searching for a functional role for ovarian glycosaminoglycans we examined the possibility that these substances may modulate the activity of the LH-stimulated adenylate cyclase in the follicle, and thus participate