The effects of narcotics on tissue oxidations

Abstract

The effects of narcotics (luminal, chloretone and evipan) on respiration of tissue-slices have been studied. Luminal inhibits brain respiration more in presence of glucose, lactate and pyruvate than in presence of other substrates. Inhibitions of brain respiration by narcotics are steadier when the [K+] of the medium is high. The inhibition due to chloretone develops rapidly after its addition, and has no temp. coefficient. Substrate concn. does not influence inhibitions by narcotics. The variation with narcotic concentration of the inhibition of respiration follows a sigmoid curve. Narcotics inhibit oxidations by slices of liver, kidney and diaphragm; among the processes affected are the oxidation of butyrate by liver, and that of alanine by kidney. Narcotic concns. which produce narcosis in vivo are of the same order of magnitude as those which inhibit measurably the resp. of the cerebral cortex in vitro.