Abstract
Conclusions
A comparison of the blood pressure rises in the electronarcotised and test animals during electronarcosis and after the injection of 10-5 g adrenaline (Fig. 3 I and II) shows that the rise during electronarcosis (after elimination of the vagus effect) can be explained only for a small part by hormonal mechanisms. It must be mainly a nervous phenomenon.
The considerable drop in pressure, which occurs when the high initial current is reduced, may be due to a period of decreased responsiveness of the sympathetic system after the strong stimulation. Normal stimuli and those set up by the lower maintenance current would then be unable to maintain the high or even the normal blood pressure. This is supported by the observation that, when electronarcosis is repeated at intervals of 10 minutes, this drop tends to become more marked.
The second maximum in blood pressure (Fig. 1) may be caused by impulses produced in the sympathetic by the smaller maintenance current, after this system has recovered from the effects of the high initial current.
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