Emotional Stimulation of Adrenal Secretion

I N 1891 Jacobi described nerves branching from the splanchnics ‘and supplying the adrenal gIands .I Six years later Biedl found that these nerves conveyed vaso-dilator impulses to the glands, and suggested that they probably conveyed also secretory impulses.2 Evidence for this suggestion was presented the following year by Dreyer, who demonstrated that electrical stimulation of the splanchnics below the diaphragm produced in the adrenal blood an increased amount of substance raising arterial blood pressure and that this result was independent of accompanying vascular changes in the glands.3 The work of Dreyer has been confirmed by Tscheboksaroff 4 and by Asher. The conclusion is justified, therefore, that adrenal secretion is under control of the thoracico-lumbar autonomic (sympathetic) system. The phenomena of a major emotional exhibition in an animal indicate the dominance of sympathetic impulses. When, for example, a cat becomes frightened, the pupils dilate, the stomach and intestines are inhibited, the heart beats rapidly, the hairs of the back and tail stand erect all signs of nervous discharges along sympathetic paths. Do not the adrenal glands share in this widespread subjugation of the viscera to sympathetic control? In order to test this suggestion the natural enmity between two laboratory animals, dog and cat, was utilized. The cat, fastened to a comfortable holder, was placed near a barking dog. Some cats