Effects of VX, Atropine,and 2-PAMCl on the Isolated Perfused Heart.

摘要

The effects of VX,atropine,and 2-PAMCl have been studied in 25isolated canine hearts perfused with autologous blood, VX produced a profound bradycardia and decrease in contractile force but had no effect on perfusion pressure. Atropine administered after VX restored heart rate to near control but did not significantly increase contractile force. 2-PAMCl added to the perfusate after VX likewise caused an increase in heart rate to near control,but in addition increased contractile force to greater than control levels. Atropine administered following VX and 2-PAMCl caused a tachycardia but no increase in contractile force. 2-PAMCl administered following VX and atropine caused a moderate increase in heart rate and an additional increase in contractile force. Assays of whole blood,plasma,and red blood cell cholinesterase of blood samples from the hearts showed that after VX,cholinesterase drops to zero. Atropine does not increase cholinesterase activity after VX;however, 2-PAMCl restores cholinesterase to 20to 40percent of control values.