Adrenal catecholamines in E. coli endotoxin shock

¹ Department of Physiology, University of Illinois College of Medicine, Chicago, Illinois

In dogs with left adrenal cannulation, administration of 1 mg/kg of purified E. coli endotoxin resulted in a decrease in mean blood pressure and adrenal blood flow. These changes were accompanied by significant increases in levels of epinephrine in adrenal venous blood. Release of epinephrine by the adrenals in endotoxin shock was due to a neurogenic mechanism, since sectioning of the splanchnic nerves prevented secretion of epinephrine. The rise in epinephrine output from an intact adrenal was noted to occur only in the presence of a significant decrease in arterial blood pressure; therefore endotoxin causes adrenal stimulation from reflexes initiated by the hypothalamus or peripheral baroreceptors.