STERIC ASPECTS OF ADRENERGIC DRUGS. III. SENSITIZATION BY COCAINE TO ISOMERS OF SYMPATHOMIMETIC AMINES

¹ College of Pharmacy, The Ohio State University, Columbus, Ohio

The influence of cocaine (5 mg/kg i.v.) on the nictitating membrane effects of D(-), levorotatory, and L(+), dextrotatory, isomers of norepinephrine, epinephrine, phenylephrine and cobefrin was studied in normal and reserpine-pretreated (5 mg/kg i.p., 24hr) spinal cats. It caused marked sensitization to all D(-) isomers in the following order of magnitude: D(-)-norepinephrine D(-)-cobefrin D(-)-phenylephrine D(-)-epinephrine, but caused little or no sensitization to L(+)isomers. A similar pattern of sensitization was obserbed with pressor effects, but differences between the D(-) isomers were less marked. For the amines studied, sensitization by cocaine appears to be stereospecific in favor of isomers with the D configuration at the carbon.