Studies on Cryptolepine

Abstract

The inhibitory effects of cryptolepine and its interaction with prostaglandin E₂, indomethacin, adrenaline and acetylcholine have been investigated on the isolated rabbit duodenum.

Cryptolepine (10-20 µg ml^-1) or adrenaline (0.5-1 µg ml^-1) or indomethacin (10-20 µg ml^-1) abolished or reduced pendular contractions and relaxed the tissue. Cryptolepine (20 µg ml^-1) produced an initial contraction before relaxation of the tissue.

Cryptolepine (10-20 µg ml^-1) abolished responses of the duodenum to added prostaglandin E₂ and acetylcholine, but failed to reduce prostaglandin production.

The results suggested that cryptolepine antagonises prostaglandin, but has no inhibitory effect on its synthesis or release.