P27 CAN HORMONE THERAPY PALLIATE THE SHORT BOWEL SYNDROME? A.Mit- chell, J.Collin. Nuffield Department of Surgery, Oxford-Xi%&-- slty, John Radcliffe Hospital, Oxford, UK.

-Artificial pacing of' inteitinal electrical activity enhances intestinal absorption and palliates the short bowel syndrome in dogs. Reversal of intestinal segments has ameliorated the syn- drome in man and a hormonal mechanism has been suggested. Modifi- cation of electrical activity and enhanced absorption might be possible usin hormones. Our aim was to measure and correlate changes in (a 4 intestinal absorption and (b) intestina? electri- cal activity produced by reversed luminal flow and by hormones. A 75 cm segment of jejunum was isolated in 4 dogs. Electrodes were sutured to the serosa and abdominal stomata fashioned. A so- lution of 90 mmol/l NaCl and 100 mmol/l glucose was perfused at 2.9 ml/min and effluent collected from the opposite stoma. The effects of retrograde perfusion and of intravenous vasopressin (1.2 U/kg/h), somatostatin (2.5 mcg/kg/h) and prostaglandin El (PGE 1) (3.5 mcg/kg/h) were observed. Non-absorbable isotope mar- kers were used to measure transit time and absorption. Electrical recordings from the small intestine were made throughout. Retro- grade perfusion increased absorption of water (1.34 to 1.71 ml/ min), sodium (0.12 to 0.17 mEq/min) and glucose (0.12 to 0.14 mmol/min( (p10.001), reduced the percentage of slow waves with associated fast wave electrical activity (14.5 + 3.4 to 4 + 1.6; mean + SEM) (~(0.01) and delayed transit (9.2 ; 1.6 to 13-9 + 2.9 mins) (~(0.01). Similar effects were produted by vasoprei- sin and somatostatin. The reduction in intestinal blood flow which these hormones produce may have limited their ability to increase absorption. However PGE 1, which increases mesenteric blood flow, failed to alter absorption or electrical activity. We conclude that intestinal electrical activity and absorption are related and that both can be modified by physical and hormo- nal factors. Hormone therapy might aid nutrition in patients with short bowel syndrome.

P28 CHANGES OF THE ABSORPTION RATE INDUCED BY THE IMMUNE RESPONE: J.Seifert*,R.Ganser. A.Pfleiderer, W.Brendel.Institute for Sur- gical Research, GroShadern Munich and Experimental Surgery of the University of Kiel*.

With the knowledge many patients are immunized against anti- gens of the normal food.The aim of the investigations in ani- mals was to test the influence of sensitization on the absorp- tion of the antigen. For this purpose rabbits were imrmnized a- gainst humn gamma globulin (HGG), till precipitating antibo- dies could be detected in the serum of animals. The absorption was determined by means of radioactively labelled HGG. From the restactivity in the gut 4 hours after the application the ab- sorption rate could be calculated. In the 1. control group with- out immunization the absorption rate was observed in the same way. The 2. control group &as immunized but absorbed human serum albumin (HSA). In normal not immunized animals the absorption was found at.88% of the applied HGG within 4 hours. The immuni- zation of the animals induced a marked and significant reduction of the absorption of HGG to 57%, whereas a non antigenic subs- tance was absorbed in the same animals with an absorption rate of 80%. In a second experiment it could be shown that this re- duction depends on the degree of immunization. Animals with a high antibody titer present the lowest absorption, animals with a small titer show a small reduction and tolerant animals even an improved absorption of this specific antigen. The results show that the absorption of nutritonal proteins is regulated by the immune response of the organism, but not by the rule of "all or nothing" but by the degree of immunization.

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