Gastric mucosal barrier in the rats fed with protein deficient diet or treated with carbon tetrachloride.

The effects of protein deficient diet and liver damage on the gastric mucosal barrier were studied in 32 Sprague-Dawley rats. The animals were divided into 4 groups according to their dietary regimens, CCl4 induced liver damage and/or serotonin administration. Group 1 (control) was fed standard rat chow. Group II was fed a nonprotein diet for 2 weeks. Group III and IV were fed standard rat chow and given 1 ml of CCl4 per/Kg body weight intraperitoneally twice weekly for 12 weeks. Rats in Group IV were also injected with 20mg per/Kg of serotonin intraperitoneally 30 minutes prior to surgery. After pyloric ligation, an acid test solution composed of 100 mM HCl, 10mM NaCl, 5mM KCl and 5g per litre of PEG was instilled into the stomach and fluxes of Na +, K +, H + and Cl-ions across the gastric mucosa were measured. Compared to Group I, rats in Group II, III and IV demonstrated an increased net negative hydrogen flux (p less than 0.05). An increased net negative chloride flux (p less than 0.05) was also demonstrated in Group II and IV, but no increase was noted in Group III. There were no significant differences in fluxes of sodium and potassium ions. As mentioned above, a lack of protein in the diet, liver damage or both, renders the gastric mucosa of the rat more susceptible to injury. In the gastric mucosa of these rats, there have occurred more increase in the negative net fluxes of hydrogen and chloride ion, which may indicate the reduction of defence mechanism against a mucosal damage.