SOMATOSTATIN BINDING TO DISSOCIATED CELLS FROM RAT CEREBRAL-CORTEX

A method has been developed for the study of somatostatin (SS) binding to dissociated cells from rat cerebral cortex. Binding of [I-125][Tyr11]SS to cells obtained by mechanical dissociation of rat cerebral cortex was dependent on time and temperature, saturable, reversible and highly specific. Under conditions of equilibrium, i.e., 60 min at 25-degrees-C, native SS inhibited tracer binding in a dose-dependent manner. The Scatchard analysis of binding data was linear and yielded a dissociation constant of 0.60 +/- 0.08 nM with a maximal binding capacity of 160 +/- 16 fmol/mg protein. The binding of [I-125][Tyr11]SS was specific as shown in experiments on tracer displacement by the native peptide, SS analogues, and unrelated peptides.