Effects of upper abdominal sympathectomy on gastric acid, serum gastrin, and catecholamines in the rat gut.

Selective upper abdominal sympathectomy increased basal acid output in rats but was without effect on stimulated acid output, serum gastrin concentration, and gastric mucosal histidine decarboxylase activity. The sympathectomy was verified by fluorescence histochemistry and determination of tissue catecholamines. A drastic reduction in tissue noradrenaline, adrenaline, and dopamine levels occurred after sympathectomy, and fluorescence microscopy showed a complete loss of adrenergic nerve fibers. Vagotomy reduced catecholamine levels in the stomach wall by 50% but did not affect the catecholamine content in the pancreas and small bowel. Surprisingly, combined vagotomy and upper abdominal sympathectomy resulted in lower catecholamine levels than sympathectomy alone in extragastric but not in gastric tissues.