Der enzymatische Abbau von Bernsteinsäure-dicholinester in der menschlichen Lunge

Publisher Website
Google Scholar
Abstract
A presentation is given of the present hypothesis for the action of succinyl dicholine, in which this muscle relaxant is hydrolysed by the cholin-esterase (pseudocholinesterase) of human serum, and occasional instances of intermediate action in the form of a prolonged apnoea are caused by a genetically determined ''atypical pseudocholinesterase'' or a mixed form of this and normal esterase. The existence of an inhibitory protein, which was described earlier in human serum is then discussed. The drug is not hydrolysed by serum, but an enzyme is described in the lung, which rapidly hydrolyses succinyl dicholine to the monoester. The monoester has only 1/8-1/10 of the relaxing activity of the diester and it cannot be degraded further in the lung. Under standard conditions the reaction is complete in 10-15 min.; the different phases of the reaction were followed by paper chroma-tography; the study of 68 lungs showed a decrease in the rate of reaction with increasing age of the donor. The similarity of the acetyl-cholinesterases of lung and serum (both are inhibited in the same way bv succinyl dicholine) is discussed.