抄録
In order to acknowledge the rôle of the accelerated epinephrine discharge by piqûre on the blood sugar increase and the fluctuation in the blood pressure, simultaneously occurring, the present researches were made. A continuous intravenous infusion of adrenaline hydrochloride was made into dogs, the suprarenals of which were either exptirpated or previously demedullated, associated with puncturing the floor of the fourth ventricle or without it. The amounts of adrenaline infused per kilo and per unit of time were adjusted to simulate the epinephrine liberation from the glands on piqûre. All the experiments were carried out without fastening, narcotizing, or exercising pain. And the results were also compared with the data previously presented by the writers.
(1) The blood pressure:
The abrupt elevation in the mean arterial blood pressure with or without a preceding transitorily rapid fall was equally recorded immediately after piqûre in normal dogs and in dogs with complete abolishing of the epinephrine secretion without and with simultaneous infusion of adrenaline simulating the hyper-epinephrinaemia of piqûre, as well. The accelerated epinephrine output due to the piqûre, has no bearing upon the abrupt, great alterations in the blood pressure taking place soon after the puncture.
The mean blood pressure in dogs with the demedullated suprarenals was not to be affected practically by the adrenaline infusion, imitating the epinephrine secretion by piqûre; the greatest velocity applied was only a little larger than the threshold value for eliciting the pressor effect. The blood pressure in dogs, lacking the medullisuprarenal functions, was apt often to descend gradually after the piqûre, while almost no descent occurred when it was combined with the adrenaline infusion made as a copy of the actual piqûre-epinephrinaemia, or when the piqûre was made in normal dogs. These facts led us to conclude that the blood pressure should after piqûre gradually suffer some disturbances, unless it were not protected by increasing the epinephrine output, simultaneously occurring.
(2) The blood sugar:
The piqûre is capable of causing hyperglycaemia of a certain magnitude in dogs lacking epinephrine output, only it is somewhat inferior to that detectable in normal dogs. Infusion of adrenaline hydrochloride made as a copy of the hyper-epinephrinaemia by piqûre is also capable of causing increase of the blood sugar of about the same magnitude and duration as the above case. When both the procedures are done together, the hyperglycaemia in creases in magnitude which expresses simply the sum of both and almost closely aporoaches to that causable by piqûre in normal dogs.
The hyperglycaemia by piqûre in normal dogs was thus quantitatively determined as simply the sum of two items, that is that by epinephrine liberated by piqûre and that by the nervous impulse coming down through the splanchnic nerves chiefly, except that designated to the suprarenals. And both the factors have almost a similar share in provoking the hyperglycaemia of that magnitude.
