In order to elicite the rôle possibly played by the augmented epinephrine secretion by insulin in altering the blood sugar level, the mean arterial blood pressure, the pulse rate, the body temperature, the clinical symptoms etc., the present writer has attempted to give insulin (Toronto) intravenously into dogs, normal and with the demedullated suprarenals, in uniform dosage of 5 units per kilo of body weight, and in fact:
Insulin alone into normal dogs; few in number, because the experiments by Yen, Aomura and Inaba can be utilized also as the control according to circumstances.
Insulin alone to the dogs with the demedullated suprarenal glands;
Insulin to the dogs, so operated on, with the continuous injection of the physiological saline solution at the velocity of 1 c. c. per minute, with which the saline solution of adrenaline hydrochloride was infused to the dogs with the demedullated suprarenal capsules with or without injection of insulin;
Adrenaline hydrochloride solution to the dogs with the deme-dullated suprarenal capsules with the velocity of 1 c.c. per minute but at the same time with the same velocity, as far as possible, rê adrenaline hydrochloride itself to that with which epinephrine is liberated from the suprarenals when poisoned with 5 units insulin per kilo body weight;
And lastly, adrenaline hydrochloride solution in the above described manner, and insulin intravenously to the dogs with the deme-dullated suprarenal capsu'
The results may be summarized as follows then:
Adrenaline hydrochloride, intravenously introduced in the above described manner and magnitude, is capable of causing the hyperglycaemia of a certain intensity, an accelerated pulse rate, and an increase in the body temperature.
The demedullation of the suprarenal capsules increases the intensity of clinical poisoning symptoms, of hypoglycaemia due to insulin; The pulse rate, on the contrary, shows rather a tendency to decrease, and the body temperature decreases too.
Combined injection of insulin at once and of adrenaline hydroch-loride solution in imitating the augmented epinephrine liberation in the so poisoned normal dogs, brings about in dogs with the deme-dullated suprarenal glands, poisoning symptoms almost similar to those occasionable in normal dogs poisoned with insulin alone, rê the clinical symptoms, the blood sugar content, the heart rate and the body temperature.
Of the blood pressure the same might be the case, but it is difficult to say with definiteness. Hypertonic effect of adrenaline hydrochloride solution in the manner and magnitude, above described, was doubtful, and there were scarcely any material differences rê the blood pressure fall due to insulin between the normal dogs, and those with demedullated capsules, with or without the infusion of adrenaline hydrochloride solution in the above described manner.
Thus it is clearly elucidated that the augmented secretion of epinephrine on poisoning with insulin is acting to lessen the fall of the blood sugar content, and compensates the fall of the pulse rate and of the body temperature. This has been here quantitatively proved, that is the intravenous introduction of adrenaline hydrochloride, if done to replace as accurately as possible, the epinephrine output during the insulin poisoning, can completely compensate the loss of the medulla of the suprarenal glands rê the blood sugar content, the heart rate and the body temperature.
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