Non-neurogenic stimulation of adrenomedullary secretion during endotoxicosis in the one day old rat.

In both newborn and twenty day old rats, bacterial (S. enteritidis) endotoxin caused a marked decrease in adrenal epinephrine and norepinephrine. Catecholamine release was prevented by ganglionic blockade in 20 day old, but not 1 day old animals, indicating that the release in the neonatal rat is "non-neurogenic." The amount released was physiologically significant: equivalent to 20 micrograms/kg by i.v. administration. Two possible mechanism known to promote non-neurogenic secretion are hypoxia or histamine release, both of which can occur during endotoxicosis.