CONCANAVALIN A BINDING TO BRAIN PARTICULATE PREPARATIONS AND ITS EFFECT ON ADENYLATE-CYCLASE

[3H]-Concanavalin A [con A] binding to [rat] brain particulate preparations measured by a filtration technique showed a characteristic regional specificity with the caudate-putamen area exhibiting the greatest density of con A binding sites. The synaptic membranes were the most highly enriched of the subcellular fractions examined in terms of lectin-binding glycoproteins. Con A also inhibited the basal adenylate cyclase activity of cerebral, cerebellar and caudate-putamen particulate preparations in a concentration-dependent manner. This lectin sensitivity of the adenylate cyclase was apparently an intrinsic property of the enzyme complex, since a detergent dispersed preparation of the cerebral cortical enzyme was equally inhibited by con A. One of the membrane con A binding sites in brain tissue may be a component of the adenylate cyclase system.