THE PRESERVATION OF SUBSTANCE P BY LYSERGIC ACID DIETHYLAMIDE

Lysergic acid diethylamide (LSD) enhances the response of guinea pig ileum to substance P, but not to histamine, and prevents substance P from being broken down by guinea pig brain extract, though not by chymotrypsin. Other substances tested—eserine, morphine, mescaline, chlorpromazine, ergometrine, strychnine, and 2-bromo-LSD—did not produce this effect. Oxytocin was not degraded by brain extract. The inhibitory effect of LSD on substance P destruction was counteracted by 2-bromo-LSD, suggesting a potential link to LSD's pharmacological actions.

Study at a glance

Abstract

Lysergic acid diethylamide (LSD) potentiated the response of guinea‐pig ileum to substance P but not to histamine. It also inhibited the disappearance of substance P when incubated with guinea‐pig brain extract but not when incubated with chymotrypsin. Eserine, morphine, mescaline, chlorpromazine, ergometrine, strychnine and 2 bromo‐LSD did not have this effect. Oxytocin was not destroyed by brain extract. The inhibition of the destruction of substance P by LSD could be antagonized by 2 bromo‐LSD. This effect of LSD may have some relation to its pharmacological actions.