Influence of ischemia on noradrenergic nerves in the terminal colon of humans and rats.

Sympathetic innervation was examined by fluorescence histochemistry in the aganglionic colon from 13 patients with Hirschsprung's disease. The 2 aganglionic colons subjected to ischemia were virtually devoid of fluorescent noradrenergic nerves. However, the sympathetic nerves of the ischemic colons fluoresced brightly after an in vitro loading of noradrenaline. Such being the case, we investigated the influence of ischemia on the sympathetic nerves in the distal colon of rats. Even 1 h of ischemia depleted the fluorescence of sympathetic nerves in the rat distal colon. Loading of noradrenaline resulted in restoration of the fluorescence in the sympathetic nerves in the distal colon subjected to 2, but not 3 h, of ischemia. The dense noradrenergic innervation, together with the occurrence of small nerve bundles, was characteristically evident in the longitudinal muscle of the distal aganglionic colon from children with Hirschsprung's disease.