Mongrel adult 29 dogs were used. They were anesthetized by the intravenous injection of 0.3per cent solution of Isozol. In denervated kidney, the left renal blood flow measured by an electromagnetic flow-meter and the aortic blood pressure by an electric manometer were recorded coincidentally, and a nervous mechanism on the renal blood flow was investigated.
Influence of Adrenalin upon the renal blood flow in these cases in which the left renal nerves and the left spinal ganglions of Thll to L 1 were extirpated, and in which the left anterior and posterior roots of them were severed respectively was observed. The results obtained are as follows.
In 3 cases extirpating the left renal nerves, the left renal blood flow was decreased about 50per cent of the control amount of the renal blood flow, in comparison with the renal blood flow in the innervated cases which was decreased about 20per cent by the intravenous injection of Adrenalin.
A manifest difference of the influence of Adrenalin was observed upon the renal blood flow between the innervated and the denervated cases, and the difference seems to be due to effects of the renal denervation.
Therefor, it is suspected that an intrarenal autoregulation exists a modulator of the renal blood flow.
In the other 17 cases severing the left anterior and posterior roots of them, with careful surgical procedure, the pressure and the renal blood flow were measured twice at one week and three weeks after the operation. In all these denervated cases, the pressure was given a rapid sharp rise, and the renal blood flow was decreased under 20 percent by the injection of Adrenalin. Therefore, effects of Adrenalin to both the pressure and the renal blood flow, even in all these cases, were observed obviously.
The most decrease in the renal blood flow after the injection of Adrenalin was found in the cases extirpating the spinal ganglions, and the most late recovery of the renal blood flow decreased was observed in the cases severing the anterior roots. In the cases severing the posterior roots, the recovery of the decreased renal blood flow was similar to the one in the innervated cases decreasing the renal blood flow by injection of Adrenalin.
An influence of Adrenalin upon the renal blood flow in both the innervated and denervated cases was observed to make each different decreased renal blood flow.
Accordingly, the difference seems to be due to an influence of the nerves severed and extirpated respectively, systematically. It is supposed that the influence of Adrenalin upon the renal blood flow of the cases at three weeks after the operation resembles to the one of the innervated cases rather than the one of the cases at one week.
Hence, it is thought that blood flow regulation of the renal vessels was compensated with other factors except these nerves severed and extirpated here, gradually after the operation.