STUDIES ON THE PHARMACOLOGY OF TETRAETHYLPYROPHOSPHATE

¹ Pharmacology Branch, Chemical Corps Medical Laboratories, Army Chemical Center, Maryland

An attempt has been made to relate the effects produced by TEPP on the mechanical response of the gastrocnemius-soleus-tibialis anticus mnuscle group and on the spike potential of the sciatic nerve of the cat with changes in cholinesterase activity in these two sites. When nerve conduction and muscular response of one leg had been abolished, the enzymatic activities in the corresponding nerve and muscle of the opposite leg were greatly reduced but still detectable. After nerve conduction and muscular response had returned in the stimulated leg, the cholinesterase activities in this nerve and muscle were at the levels found in the opposite leg at the time at which function was absent.

It is possible that TEPP, when used as a tool in pharmacological or physiological research, produces effects on neuromuscular function which are not related necessarily to inhibition of cholinesterase. Therefore, this compound should be employed in this capacity with certain reservations.