Decontamination with polymyxin, tobramycin, vancomycin, and amphotericin B during anastomotic wound healing is safe and effective in the prevention of esophagojejunal anastomotic leakage after total gastrectomy.

Transforming growth factor a (TGF-a), a protein secreted by transformed cells and related to epidermal growth factor (EGF), was tested for its effects on gastric acid secretion. Guinea pig gastric mucosae were mounted in Ussing chambers and the rate of acid release was monitored by the pH-stat method. When administered prior to the secretagogue, TGF-a prevented the histamine-induced increase in the rate of acid secretion. Similarly, TGF-a caused a decrease in the rate of acid release in tissues that had already been stimulated with histamine. These data show that TGF-a inhibits gastric acid secretion in a manner similar to EGF and that the two growth factors share at least one physiological action unrelated to their mitogenic properties.Transforming growth factor a (TGF-a) is a protein that is structurally and functionally similar to epidermal growth factor (EGF). The overall amino acid sequences of these two peptides are about 33% homologous, and there is an even more highly conserved core region (1-4). TGF-a competes with EGF for binding to a receptor on the surface of cultured cells and isolated membranes (5-10), and an antibody to the EGF receptor blocks the mitogenic activity of conditioned medium containing TGF-a (11). TGF-a (or a partially purified preparation containing TGF-a) stimulates phosphorylation of tyrosine residues on the EGF receptor and other substrates (9, 12, 13). TGF-a, like EGF, is mitogenic for cultured cells (5,9,14) and in conjunction with transforming growth factor f3 permits anchorage-independent growth of NRK cells (7-10). In vivo, both TGF-a and EGF cause precocious separation of eyelids of newborn mice (15,16).In addition to these growth-related phenomena, EGF is known to inhibit gastric acid secretion (17-22). We have previously (22) used an Ussing-chamber preparation of guinea pig mucosae to study EGF's antisecretory properties. This system has the advantages over whole-animal models that the concentrations oftest substances can be precisely controlled, that secondary effects arising from interaction of the test substances with other organs are eliminated, and that much smaller quantities of reagents are required. These properties make the in vitro guinea pig model ideal for studying the effects of peptides related to EGF.One possible explanation for the coexistence of EGF and TGF-a is that, besides their shared mitogenic properties, they might also have biological activities unique to each peptide. To determine whether inhibition of acid secretion is one of these unique properties, we examined the effect of TGF-a on the Ussing-chamber preparation of guinea pig mucosa. We report here that TGF-a is capable of inhibiting histaminestimulated acid secretion in a manner similar to EGF. MATERIALS AND METHODSStomachs from young (200-to 250-g) female guinea pigs were hemisected along the greater and lesser curvatures and placed mucosal-surface down on a piece of Parafilm. The outer muscle layers were removed with fine forceps and both halves of the mucosa were mounted separately ...

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The blood flow of the alimentary tract in anesthetized dogs was measured with radioactively labeled 15-micron microspheres before and after i.v. application of the gastrointestinal hormones glucagon, vasoactive intestinal polypeptide (VIP), secretin, and somatostatin. After 5 min glucagon in a dose of 75 micrograms/kg bolus + 5 micrograms/kg X min-1 infusion increased significantly the blood flow in liver, stomach, duodenum, jejunum, ileum, and colon as well as the cardiac output by 160%, 761%, 662%, 576%, 817.3%, 320%, and 108%, respectively. A dose of 3 ng/kg X min-1 resulted in reduction of the circulation in liver, gastric fundus, duodenum, and colon by 27.7%, 19.1%, 16.2%, and 10.7% after 5 min while the cardiac output was not affected. Vasoactive intestinal polypeptide (VIP) infused in a dose of 3.3 pmol/kg X min-1 for 5 min increased the blood flow in the pancreas by 30% and reduced it in the spleen and gastric corpus by 26.9% and 41.5%, respectively. Secretin, another member of the glucagon family, after a 5-min infusion of a dose of 0.5 CU/kg X min-1 increased the cardiac output by 49.96% and the renal circulation by 120.7%. In the gastrointestinal tract circulation of the gastric antrum was stimulated by 474%, of the duodenum by 93.5% and of the ileal mucosa by 178%. Infusion of the pancreatic hormone somatostatin (3.5 micrograms/kg bolus followed by infusion of 3.5 micrograms/kg X h-1) increased the blood flow in the liver by 13%, in the pancreas by 23.15%, and in the spleen by 29.8%, while it reduced it in the fundic mucosa by 17.1% and corpus mucosa by 28.8%. In summary, the gastrointestinal hormones examined exert marked and distinct effects on the circulation of the gastrointestinal tract, each hormone in different parts of the digestive tract. Thus, the local microcirculation of the gastrointestinal tract seems to be subject to hormonal in addition to nerval control.