Abstract
In the communication on the effects of subcutaneous injections of magnesium salts, John Auer and I stated that a dose of magnesium sulphate slightly larger than 1.75 gram per kilo is surely fatal for the rabbit. Lucas and I showed later that in nephrectomized animals the toxicity of the salts is greatly increased. At the April meeting I conducted an experiment demonstrating that in nephrectomized animals magnesium sulphate can become toxic even when given by mouth. These lines of experimentation have shown that the toxicity of magnesium salts depends upon the normal activity of the kidneys. I wish now to report the results of a series of experiments in which the effect of an increased renal activity was studied.
Briefly stated the results were as follows: A dose of 2 grams of magnesium sulphate per kilo is absolutely fatal for the rabbit; the animal dies of respiratory paralysis in less than an hour. All the animals recovered from the effects of such a dose, however, if an intramuscular injection of diuretin was given soon after the subcutaneous injection of the magnesium salt. Diuretin is theobromin and acts as a diuretic. The deeply narcotized animals usually urinate about fifteen or twenty minutes after its injection; by that time, at least, the bladder can be felt to be full. The largest dose that should be given is about 0.1 gram. In larger doses diuretin itself is liable to become toxic.
In cases in which the dose of the magnesium salts exceeded 2 grams per kilo the injection of diuretin alone could not save the animals. But if in addition to the diuretin an intravenous infusion of 0.9 per cent. solution of sodium chloride was instituted, animals were seen to recover even from doses of magnesium salts amounting to as much as 2.25 grams per kilo.
Get full access to this article
View all access options for this article.