Relationship between plasmatic levels of sarin and cholinesterase inhibition in rats exposed to sarin vapors.

Abstract

In our study we monitored plasmatic levels of sarin and changes in cholinesterase activities in rats after exposure to sarin vapors at low concentration. Rats were exposed to sarin in inhalation chamber at concentration 1.25 or 2.5 microg/l for 60 minutes. The acetylcholinesterase activity was measured in erythrocytes and in different brain regions (frontal cortex--FC, pontomedullar area--PM, basal ganglia--BG). Butyrylcholinesterase activity and sarin levels were measured in plasma. Acetylcholinesterase activity in erythrocytes as well as butyrylcholinesterase activity in plasma were significantly decreased in both groups of animals after intoxication with sarin. In brain, the significant decrease in acetylcholinesterase activity was measured in FC and PM for both groups. In group exposed to higher concentration of sarin vapors, the plasmatic level of sarin was nearly 2 x higher than in group exposed to sarin at concentration 1.25 microg/l. The linear dependence between plasmatic levels of sarin and AChE activity was assayed in FC region of brain and in erythrocytes, exponential relationship in PM region of brain and for BuChE activity in plasma.