THE RELEASE OF ADRENALINE AND NORADRENALINE FROM THE ADRENAL GLAND OF THE CAT BY ACETYLCHOLINE

The adrenal glands of atropinized cats were depleted of their content of adrenaline and noradrenaline by repeated intravenous doses of acetylcholine. In each experiment there was a similar percentage loss of both amines. This was irrespective of the degree of depletion, which ranged from 7.1% to 86.5%. In some experiments, adrenal blood was collected and it was found that the percentage of noradrenaline in the adrenal venous effluent (mean 62.0%) was similar to that in the amine lost from the depleted gland (mean 63.7%). In some experiments, the adrenaline and noradrenaline lost from the gland could be recovered quantitatively in the adrenal blood. The results indicate that, under these experimental conditions, synthesis is not taking place concurrently with the liberation of amines or that it is taking place so slowly as not to be detected.