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Colonic permeability was studied in vitro in patients subjected to colectomy because of ulcerative colitis and in control patients undergoing colonic resections for cancer.The mucosal layer from fresh colonic segments was stripped and mounted in Ussing diffusion chambers containing modified Krebs buffer solution. The mucosa to serosa passage of the marker molecules 14C-mannitol and ovalbumin was measured for 120 min.Marker passage was significantly increased in colitis patients compared with control patients, irrespective of age, sex, duration of disease, and treatment. Marker passage was further increased in patients with acute colitis. The increased colonic permeability may be explained by inflammation and the resultant loss of mucosal integrity. The increased permeability to ovalbumin implies that permeability to luminal macromolecules, such as bacterial products and other antigenic substances, might be increased in colitis.The results suggest a derangement of the colonic barrier, as evidenced by an increased mucosal permeability in both chronic and acute colitis.

Anaesthetized animals are often used in studies of gastric secretion. We have examined the effect of anaesthetics on the acid output in gastric fistula rats and pylorus-ligated rats, both vagally intact and denervated. Diethyl ether, chloral hydrate, and mebumal effectively reduced both basal and stimulated acid output in fistula rats. The acid output in pylorus-ligated rats was greatly reduced by the anaesthetics. In vagally denervated rats local nervous reflexes are thought to play an important role in the acid secretory response to pylorus ligation. Anaesthetic drugs suppressed acid output in both vagally intact and vagally denervated rats. The possibility of an action on intramural neurons cannot be excluded. The neuro-suppressive effect of anaesthesia should be considered in studies of gastric acid secretion.

Sympathectomy has been used to study the role of the sympathetic nervous system in the control of gastric acid secretion. Conflicting results may reflect differences in the sympathectomy procedures used. In a previous study we showed a reduction of catecholamines by more than 90% in the gut wall of the rat after surgical upper abdominal sympathectomy. The aim of the present investigation was to ascertain whether chemical sympathectomy was equally effective and whether total denervation, including combined chemical and surgical sympathectomy together with bilateral truncal vagotomy, would lower the catecholamine levels further. The results showed that chemical sympathectomy reduced noradrenaline levels in fundus (oxyntic) and antrum mucosa to levels similar to those after surgical sympathectomy (less than 5%), but the reduction was less pronounced in the muscle layer of the fundus and antrum and in the pancreas and spleen. Combined surgical and chemical sympathectomy did not reduce noradrenaline more effectively than surgical sympathectomy alone. Vagotomy reduced catecholamines in the stomach by about 50%; in extragastric tissues vagotomy was without effect. Total denervation, including combined surgical and chemical sympathectomy plus vagotomy, did not reduce noradrenaline levels more than surgical sympathectomy alone, suggesting that the proportion of adrenergic fibers that derive from the vagus is quantitatively insignificant but that the vagus exerts a local control of the sympathetic stores of gastric catecholamines.(ABSTRACT TRUNCATED AT 250 WORDS)

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.