Correlation of inhibitory potencies of putative antagonists for sigma receptors in brain and spleen.

The putative sigma receptor antagonists, haloperidol, HR 375, BMY 14802 and BW 234U potently inhibited both [3H]d-N-allylnormetazocine binding to sigma receptors in brain homogenates and [3H]haloperidol binding to sigma receptors in spleen homogenates. An excellent correlation of inhibitory potencies in the two assay systems was obtained. The results support the view that [3H]d-N-allylnormetazocine and [3H]haloperidol both label the same receptor populations, and suggest that sigma antagonists may be useful in elucidating physiological role(s) of sigma receptors in the nervous and immune systems.