Cholinesterase Activities in the Serum of Healthy British Children

Abstract

IN the course of some work which was being done in Germany on the effect of a liberal diet on the serum cholinesterase levels in under-nourished children¹, it was realized that there were no corresponding figures for healthy, well-nourished children available for comparison. It was therefore decided to measure the pseudo-cholinesterase activity of the serum of normal girls and boys. Blood was taken from 111 healthy children attending schools in Cambridge. These children were all between five and fifteen years old and so far as possible each year of age was represented by five girls and five boys. Preliminary experiments had shown that the activities of sera from blood obtained by ear puncture did not differ significantly from the serum activities in the same subjects when the blood was taken by venepuncture. Blood samples, therefore, were obtained by puncturing the lobe of the ear with a piece of capillary tubing and allowing the blood to fall directly into an agglutination tube, which was then quickly closed with a rubber stopper. The serum was separated in the usual way. Cholinesterase determinations were carried out in duplicate in a Warburg apparatus by the method used by McArdle², with acetylcholine chloride as substrate. Activities were expressed in c.mm. carbon dioxide/ml. serum/min.