Studies on cholinesterase. 6. The selective inhibition of true cholinesterase in vivo

Abstract
The prostigmine analog, N-p-chlorophenyl-N-methylcarbamate of m-hydroxyphenyltrimethyl-ammonium bromide (Hoffmann-La Roche Nu-1250), was found to be a selective inhibitor of true cholinesterase. Inhibition of true cholinesterase in rats,brought about by the injn. of Nu-1250, elicits symptoms indicative of acetylcholine accumulation, in spite of the undiminished activity of pseudo-cholinesterase. Thus, pseudo-cholinesterase is not essential to the hydrolysis of acetylcholine in vivo, as previous expts. have shown, nor is it capable of assuming even an auxiliary role in this process when the activity of the true cholinesterase is impaired.