[Characteristics of brain gastrin/cholecystokinin-binding proteins].

Gastrin/cholecystokinin-binding proteins were purified using the column affinity chromatography on immobilized pig tetragastrin and cholecystokinin. Immunoblotting analysis of different human tissue extracts with specific antisera obtained against gastrin-binding proteins was performed. It was found that high molecular weight polypeptide zones of 120 kDa and 35 kDa were characteristic of the brain only. Autoantisera of patients with type A gastric disease reacted with some gastrin/cholecystokinin-binding proteins in human brain and mucosa including human brain polypeptide of 120 kDa. It is supposed that there are neurospecific gastrin-binding proteins (possibly gastrin/cholecystokinin receptors in the brain).