Production of Hyperglycemia in Rabbits by Subcutaneous Injections of Magnesium Salts.

Abstract

The presence of magnesium in chlorophyll, and the important role of the latter in the metabolism of carbohydrates in plants, led us to study the effect of magnesium salts on blood sugar in rabbits. Five normal rabbits, starved for 24 hours, were injected subcutaneously with a 5 per cent solution of MgCl₂ or MgSO₄, using 5 cc. of this solution per kilo of body weight. During the experiment the rabbits were kept quiet in a tray, without restraint, and there was no struggle when the 2 cc. of blood were taken from the marginal ear vein. Such moderate bleeding does not affect essentially the blood sugar level in rabbits, as shown in a previous paper 1 .

The results of the experiments are presented in the following table:

This table shows that subcutaneous injection of magnesium salts produces a marked hyperglycemia, with a maximum in from 2 to 2 1/2 hours. In 5 1/2 hours the blood sugar is not far from its initial level, and in 24 hours it has reached a normal value. Controls, on the hemoglobin content, show that the hyperglycemia is not due to a change in blood concentration. Similarity in the results obtained by subcutaneous injections of MgCl₂ and MgSO₄ is a sufficient proof that the hyperglycemic effect is due to the magnesium ion.

Our data throw light on the understanding of the therapeutic value of magnesium salts, given per os or intravenously, especially in the treatment of nephritic uremia and eclampsia. According to Blackfan 2 , the treatment of uremia (occurring in the course of acute glomerular nephritis) by intravenous injections of 1 per cent magnesium sulphate, has given most favorable results.