THE CONTENT AND CHARACTERIZATION OF CHOLINESTERASES IN HUMAN CEREBROSPINAL FLUIDS

Abstract

Determinations of cerebrospinal fluid cholinesterase activities and fractions were made on 114 samples from 104 neurological and neurosurgical patients. Details of methods are given. Average rate of acetylcholine hydrolysis was 0.39 cu. mm. carbon dioxide per ml. CSF per min. or approximately 0.5% of the cholinesterase activity of an equal volume of blood or serum. Characterization of cholinesterase fractions, using mecholyl and benzoylcholine as substrates, showed human cerebrospinal fluid to contain specific cholinesterase with a small component of unspecified cholinesterase. Differences of blood and subdural fluid fraction patterns are demonstrated.No correlation of cholinesterase values with cerebrospinal fluid cell counts were found. Attempts to correlate cholinesterase values with cerebrospinal fluid Pandy tests and protein levels were inconclusive, although samples with positive Pandy tests and abnormally high protein levels showed a tendency toward decrease in specific and increase in unspecified cholinesterases. No correlation of cerebrospinal fluid cholinesterase values with clinical diagnoses was demonstrated with the exception of cases of craniocerebral trauma and cases treated by electric shock convulsant therapy, where a decrease in specific and a marked increase in unspecified cholinesterase fractions were observed. At acetylcholine substrate concentrations in the "physiological range" (0.01 to 10.0 μgm. %) cerebrospinal fluid cholinesterase activities were markedly reduced or absent.