Influence of atropine upon ageing and reactivation of soman inhibited acetylcholinesterase from human erythrocytes. Preliminary communication.
From human blood concentrates erythrocyte "ghosts" were prepared. These and an enzyme solution, obtained by Triton X 100 treatment of the ghosts, were reacted with 1.2.2-trimethylpropyl-methyl-phosphonylfluoridate (soman). The rate constants of inhibition of the membrane bound and solubilized acetylcholinesterase (AChE) were determined at 3 degrees C, pH 8 and 9 to be 2 X 10(7) and 1.4 X 10(7) mol-1 min-1, respectively. Ageing of the phosphonylated AChE occurred with rate constants of 3.5 X 10(-2) (ghost bound) and 1.3 X 10(-2) (solubilized) min-1 at 3 degrees C, pH 8. 5 X 10(-4) mol/l atropine decreased the ageing rate by 50%. Reactivation of the non aged phosphonyl-AChE by several pyridinium oximes was enhanced by atropine with the ghost-bound enzyme; the reactivation of the phosphonylated solubilized enzyme, however, was not affected by atropine.
D000110:Acetylcholinesterase; D001285:Atropine / Q000494:pharmacology*; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D002801:Cholinesterase Reactivators / Q000494:pharmacology*; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D012999:Soman / Q000494:pharmacology*
D002800:Cholinesterase Inhibitors; D002801:Cholinesterase Reactivators; D001285:Atropine; D012999:Soman; D000110:Acetylcholinesterase