COLONIC SHORT-CHAIN FATTY-ACIDS MEDIATE JEJUNAL GROWTH BY INCREASING GASTRIN

Colonic infusion of short chain fatty acids (SCFAs) is trophic to rat jejunum and is associated with raised jejunal gastrin concentration. T his study examined the hypothesis that the jejunal trophic effects of colonic SCFAs are mediated in part by gastrin. Forty six adult rats un derwent caecectomy to reduce endogenous production of SCFA, ileocoloni c anastomosis, and placement of a colonic infusion catheter. SCFA (70 mM acetate, 35 mM propionate, 20 mM butyrate) or saline were continuou sly infused into the colon for seven days. Rats received either a gast rin receptor blocker (L-365,260) or a control solution and animals wer e killed on day 8. SCFA infused into the colon acted systemically to s ignificantly improve jejunal structure and increase jejunal gastrin co ncentrations. Gastrin receptor blockade abolished effects of SCFA on j ejunal DNA, protein, crypt cell proliferation, and gastrin. Gastrin bl ockade did not reduce SCFA induced augmentation of villous height or c rypt depth. It is concluded that the jejunal trophic effects of coloni cally infused SCFA are mediated in part by gastrin.