Abstract
The rapid release of 3 H-estradiol from estrogen-receptor complexes at 0°C is implemented by combinations of the local anesthetic tetracaine and certain sulfated polysaccharides. The simultaneous presence of both classes of compounds was found necessary for the displacement of 3 H-estradiol to occur. A limited survey of some sulfated polysaccharides and other anionic compounds for their ability to synergize with tetracaine revealed a specificity for the charge-carrying polysaccharide. The present data support the view that the cooperative interaction of sulfated polysaccharides and certain charged hydrophobic compounds with estrogen receptors determines the ability of the receptors to bind estradiol.