THE RELATION BETWEEN THE ESTERASE ACTIVITY OF THE BLOOD PLASMA AND OF THE LIVER OF THE DOG

Abstract

Plasma cholinesterase activity in the dog was independent of sex and of total plasma protein concn. A significant degree of correlation between liver and plasma cholinesterase activities of [male] dogs was found. Calculation showed that the liver contained 5-7 times the amt. of the cholinesterase activity circulating in the blood plasma. CC14 poisoning of dogs resulted in an increase in the plasma cholinesterase activity. An analysis showed that this effect was due to the liver injury produced, that it was due to an actual increase of circulating plasma cholinesterase amounting to about 50% above normal, and that it did not reflect a failure of destruction or excretion of this enzyme. The effect of transfusions of concentrated serum albumin solns. upon the plasma cholinesterase activity of intact, splenectomized, eviscerated, and functionally hepatectomized dogs was examined. A decrease of the plasma cholinesterase activity due to dilution followed the transfusion, and in the presence of a functioning liver this fall in plasma esterase activity was followed by the release of additional enzyme into the blood, restoring the esterase level to normal in about 2 hrs. with an increase in the amt. of, circulating enzyme. No such effect was detected in eviscerated and in functionally hepatectomized dogs. The data were interpreted as indicating the existence of a considerable store of preformed plasma cholinesterase in the liver of the dog; an equilibrium seemed to govern the relation between liver and plasma cholinesterase activities; at least 25% of the circulating plasma cholinesterase activity was rapidly replaced from this hepatic store.