Gamma irradiation on rat whole blood cholinesterase

¹ Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont

Rat whole blood cholinesterase levels were followed electrometrically for 10 days following whole-body irradiation with 300 and 600 r gamma rays from a Co⁶⁰ source. Cholinesterase activity was significantly depressed in both groups after the 3rd day, reaching its lowest observed levels on the 10th day. The toxicity of acetylcholine bromide was significantly greater to mice 9 days after 300 r of whole-body gamma irradiation than in nonirradiated controls as indicated by the intraperitoneal ld₅₀ which was 294 mg/kg prior to, and 235 mg/kg after, irradiation.