Guinea-pig vas deferens preparation may contain both receptors and phencyclidine receptors

Electrically induced contractions of guinea-pig vas deferens were potentiated by sigma drugs such as d-pentazocine and d-SKF-10047 and also by phencyclidine-like drugs. Non-sigma drugs like morphine, buprenorphine, DADLE, U-50488 and l-ketocyclazocine did not potentiate contractions. The potentiations were antagonized by haloperidol and BW234U. Although the potentiation may not be definitively mediated by sigma receptors or phencyclidine receptors alone, the preparation may provide an interesting tool for studying endogenous ligands which might act like sigma or phencyclidine drugs.