A comparison of the choline-esterase activities of the blood-sera from various species

Anticholinesterase activity and charge delocalisation in “aliphatic” and “aromatic” quaternary ammonium compounds

The anticholinesterase activities of a homologous series of trimethyl(phenylalkyl)-ammonium bromides have been determined and compared with anti-acetylcholinesterase activities previously reported. The pattern of results obtained with the two enzymes differs widely. The surface activities of the compounds at a constant molar concentration was determined in order to investigate the influence of the “distribution effect” on the anticholinesterase activities of the compounds. The anticholinesterase activities of a series of polycyclic aromatic quaternary compounds have also been determined and compared with their previously reported anti-acetylcholinesterase activities. With these compounds, the pattern of results obtained with the two enzymes was similar.

Esterases of testis and other tissues

The tissues most effective in the enzymatic hydrolysis of acyl esters of p-nitrophenol by tissue extracts of the rat and dog were the liver, lung, pancreas, renal cortex, and testis; in the dog tracheal and vesical mucosae were also esterase-rich and the lens had appreciable activity. Esterase was at low concentration in the tissues of the rat for 4 and 5 days after birth, but an increase to adult levels soon took place except in the testis where the rise was delayed until puberty. The esterase values of the blood of newborn children were also low. Two patterns of activity in tissues against these esters were found. A pattern in which propionate esters were hydrolyzed most rapidly was displayed regularly by liver, lung, renal cortex, and testis of the rat and also by dog, rabbit and human serum. A second pattern with progressive effectiveness in hydrolyzing fatty acid esters of 2-carbon to 5-carbon chain length was exhibited by the pancreas of the rat, rabbit, and dog and also by rat serum. Esterase of the testis of the rat is located in the interstitial cells and its concentration seems to be directly related to androgenic hormone production. The increase of testicular esterase during puberty paralleled the increase of prostatic weight. Hypophysectomy caused a profound decrease of testicular esterase which was restored in part by gonadoptrophin. Artificial cryptorchism in the rat, causing elimination of germinal epithelium, resulted in an increase of esterase concentration although the total content of the testis slowly decreased.

Organic phosphorus poisoning in general practice; parathion, TEPP, HEPT, EPN and others

Inhalation, skin absorption or ingestion of insecticides containing organic phosphorus may result in abrupt onset of serious illness several hours following exposure. Because of the acute onset, often at night, the patients usually are observed by the first available physician rather than by an industrial physician. Prompt recognition and adequate treatment are essential to prevent death. The organic phosphorus radical has the specific effect of inactivating cholinesterase in the body. When cholinesterase is reduced below a critical level continuous stimulation of the entire parasympathetic nervous system results. The major symptoms are diarrhea, vomiting, pulmonary edema, respiratory difficulty and tonic convulsions. Myosis is frequently present and when found is almost pathognomonic, especially if associated with other symptoms. Treatment consists essentially of heroic doses of atropine or a similar parasympathetic inhibitor, plus supportive therapy. Patients who do not die recover rapidly and completely, but they should not risk re-exposure until cholinesterase activity in the blood reaches a static level which may take as long as ten weeks.