[Catecholaminergic receptors of the blood cells of schizophrenics]

The simultaneous determination of serum CA and their receptors in blood cells offers a possibility to evaluate disturbances of the DA and NA neuronal systems in man. High affinity binding sites for 3H-yohimbine in platelets, 3H-DHA on granulocytes and 3H-spiperone in lymphocytes from healthy control persons, unmedicated (n = 28), and medicated (n = 8) schizophrenics as well as from an unmedicated psychiatric control (n = 14) were investigated. Furthermore, the actual concentration of the circulating CA was determined with HPLC-ECD. In unmedicated schizophrenics as compared to controls, specific binding of 3H-spiperone to lymphocytes was markedly elevated in capacity and less in affinity as compared to controls. For beta2-receptors a significant decrease was found in capacity with no change in affinity. The changes in alpha2-receptors with a slight decrease in capacity were less distinct. The concentrations of circulating CA ranged from normal values up to a more than 3 fold increase in NA and DA, whereas A concentrations were practically unchanged. No overall change in these data was found in the medicated schizophrenic patients. 3H-spiperone binding was characteristically increased only in schizophrenics, but did not elevate above control data in the non-schizophrenic psychiatric control group. Preliminary experiments of family studies suggest that this model could be valuable as a vulnerability marker.