Effects of Bromobenzene on Mouse Tissue Sulfhydryl and Insulin-I 131 Metabolism. ∗

Summary

1) The radioactivity of I¹³¹ labeled insulin injected by tail vein into mice was rapidly concentrated by liver and kidney, and converted by these organs from TCA insoluble into TCA soluble form. 2) Overnight fasting plus bromobenzene administration resulted in significant decreases in: (a) liver and kidney non-protein sulfhydryl (reduced glutathione) concentrations, and (b) abilities of these organs to convert radioactivity of administered labeled insulin from TCA insoluble into TCA soluble form. 3) Rapid repletion of liver and kidney GSH, previously depleted by use of bromobenzene, was obtained by use of L-cysteine. The accompanying bromobenzene induced impairment of mouse tissue abilities to solubilize radioactivity of labeled insulin was not restored by L-cysteine administration. 4) Benzyl chloride administration to overnight fasted mice resulted within 2 hours in marked decrease in liver GSH concentration, not accompanied by measurable change in insulin degradation. 5) It therefore appears unlikely that insulin degradation rate varies significantly as result of physiologic variations in intracellular GSH concentrations.