Two selective inhibitors of cholinesterase

Abstract
Two new inhibitors of cholinesterase, bis(diisopropylamino) phosphonous anhydride (DPDA) and the dimethobromide of 1,5-di (p-N-allyl-N-methyl-aminophenyl)pentan-3-one (284C51), were studied. DPDA is a competitive irreversible inhibitor, selectively inhibiting pseudo cholinesterases, while 284C51 is a competitive reversible inhibitor, selectively inhibiting true cholinesterases. The selectivity of the inhibitors, I50(true): I50(pseudo)) is high, although this ratio varies considerably among mammalian species if erythrocytes and plasma are the sources of true and pseudo cholinesterases. 3 x 10-5 [image] DPDA or 10-6 to 10-5 [image] 284C51 could be used to inhibit pseudo or true cholinesterase,respectively, without measurable effect on the other. Further properties of fowl plasma cholinesterase are descr.