Effects of subclinical hydrogen sulfide intoxication on mouse brain protein metabolism

Abstract Exposure of adult female mice to 100 ppm hydrogen sulfide for 2 h resulted in a marked decrease in incorporation of labeled leucine in cerebral protein and myelin 24 and 48 h after the exposure. The reduced incorporation was accompanied by decreased lysosomal acid proteinase activity at the same time. The incorporation increased to the control level 72 h after the exposure whereas the lysosomal enzyme activity remained below the control range at the end of the follow-up period. The changes were distinct from carbon monoxide-induced changes and might have resulted from the inhibition of cerebral cytochrome oxidase activity. The delay of maximal effects to the third postexposure day might pose a potential toxicological hazard in repeated exposure to higher hydrogen sulfide concentrations.