1174
Gut 1992;33: 1174-1178
Effect of cholera toxin on the human jejunum W Petritsch, A J Eherer, U Holzer-Petsche, T Hinterleitner, E Beubler, G J Krejs
Departments of Internal Medicine and Experimental and Clinical Pharmacology, Karl Franzens University, Graz, Austria W Petritsch A J Eherer U Holzer-Petsche T Hinterleitner E Beubler G J Krejs Correspondence to: Wolfgang Petritsch, MD, Department of Internal Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria. Accepted for publication 20 January 1992
volume, and intestinal secretion after adminisAbstract In order to develop a model for secretory tration of various preparations of cholera toxin.` diarrhoea and to confirm the in vitro effects of The results of these studies, however, were too cholera toxin in man in vivo the effect of variable to lead to the use of cholera toxin as a intrajejunally administered cholera toxin secretory model. The aims of the present study was investigated in healthy volunteers. An were to characterise the dose response relationintestinal perfusion technique with an occlud- ship for cholera toxin after intrajejunal adminising balloon proximal to the infusion site was tration, to develop a standardised model of used. The jejunum was perfused under steady intestinal secretion using an intestinal perfusion state conditions with a plasma like electrolyte technique, and to expand our information on the solution containing polyethylene glycol as a action of cholera toxin on the human jejunum. non-absorbable volume marker. After two control periods of one hour each, during which water was absorbed at a rate of 104 (14) (mean Methods (SEM), n=15) and 94 (15) ml/30 cm/h, respectively, three different doses of cholera toxin SUBJECTS (6.25 rig, 12.5 tg, 25 Rg) were administered Fifteen healthy volunteers (nine men, six by bolus into the lumen of the jejunum. women, mean age 28 years, range 22-38) gave Cholera toxin reduced absorption of water and written informed consent to participate. None of electrolytes progressively over four hours and the subjects was taking any medication. A induced secretion in a dose dependent fashion. medical history, electrocardiograph, blood In the fourth hour net secretion amounted to 22 pressure, and standard laboratory findings were (23), 36 (24), and 88 (40) ml/30 cm/h (each obtained before the experiment and were found n=five) with doses of 6*25, 12-5, and 25 Fg to be negative or normal. Haematocrit was also cholera toxin, respectively. The movement of obtained 24 hours after the experiment. The sodium, chloride, and bicarbonate paralleled study was approved by the Ethics Committee of water movement. Our results suggest that the University of Graz School of Medicine. cholera toxin may serve as a secretory model in the human jejunum which might allow testing of new antisecretory agents. INTESTINAL PERFUSION (Gut 1992; 33: 1174-1178) For intestinal perfusion a tube assembly with a proximal occluding balloon was used.` The assembly with an outer diameter of 6 mm and a Secretory diarrhoea is an important health prob- mercury bag at the tip was placed in the jejunum lem particularly in developing countries. In (infusion site at the ligament of Treitz). The order to test new antisecretory agents human correct position of the tube was confirmed by models for intestinal secretion need to be estab- fluoroscopy. Because in animal studies digestive lished. Because infection with Vibrio cholerae is juices may destroy cholera toxin an occluding an important cause of diarrhoea, we decided to balloon proximal to the infusion site was used in use cholera toxin as intestinal secretagogue. order to avoid degradation of cholera toxin by Cholera toxin is the enterotoxin of Vibrio cholerae pancreatic enzymes9 (E Beubler, unpublished and while causing secretion does not impair observation). The sampling site was 30 cm distal glucose dependent sodium absorption in the to the infusion site. A fourth lumen enabled intestine and does not alter mucosal histology. I-3 removal of endogenous secretions proximal to Earlier studies with cholera toxin in man the occluding balloon. Perfusion was started in revealed an increase in stool frequency and the morning after a 12-16 hour fast. A plasma like electrolyte solution (composition in mmol/l: Na5 135, K+ 5, Cl- 110, HCO3- 30, and 2 g/l TABLE I Effect of various doses of cholera toxin (CT) on net polyethylene glycol, mean molecular weight jejunal water movement (ml/30 cmlh). Cholera toxin was 3350, as a non-absorbable volume marker) was administered as a bolus after two hours of control perfusion perfused at 10 ml/minute using a peristaltic Intrajejunal dose of CT pump. The solution was bubbled with a mixture Time (h) of 95% 02 and 5% CO2. A 30 minute equilibra25 'pg 6.25ptg 12.5 [tg after CT tion period, during which the samples were Control -54 (24) -118 (12) -135 (26) discarded was followed by six hours of collecControl -104 (12) -139 (19) -38 (22) -98 (1 1) -39 (21) -131 (22) 1 tion. Collection was performed by hand aspira2 - 120 (34)* -64 (12)* -37 (18) tion at a rate of 1.5 ml/minute using plastic 3 +4 (24)* +44 (49)* -17 (24) 4 +22 (23)*t +36 (24)*t +88 (40)*t syringes. Collected samples were pooled for each hour. After two control periods of one hour each, Quade test: *significantly different from controls, p
Gut 1992;33: 1174-1178
Effect of cholera toxin on the human jejunum W Petritsch, A J Eherer, U Holzer-Petsche, T Hinterleitner, E Beubler, G J Krejs
Departments of Internal Medicine and Experimental and Clinical Pharmacology, Karl Franzens University, Graz, Austria W Petritsch A J Eherer U Holzer-Petsche T Hinterleitner E Beubler G J Krejs Correspondence to: Wolfgang Petritsch, MD, Department of Internal Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria. Accepted for publication 20 January 1992
volume, and intestinal secretion after adminisAbstract In order to develop a model for secretory tration of various preparations of cholera toxin.` diarrhoea and to confirm the in vitro effects of The results of these studies, however, were too cholera toxin in man in vivo the effect of variable to lead to the use of cholera toxin as a intrajejunally administered cholera toxin secretory model. The aims of the present study was investigated in healthy volunteers. An were to characterise the dose response relationintestinal perfusion technique with an occlud- ship for cholera toxin after intrajejunal adminising balloon proximal to the infusion site was tration, to develop a standardised model of used. The jejunum was perfused under steady intestinal secretion using an intestinal perfusion state conditions with a plasma like electrolyte technique, and to expand our information on the solution containing polyethylene glycol as a action of cholera toxin on the human jejunum. non-absorbable volume marker. After two control periods of one hour each, during which water was absorbed at a rate of 104 (14) (mean Methods (SEM), n=15) and 94 (15) ml/30 cm/h, respectively, three different doses of cholera toxin SUBJECTS (6.25 rig, 12.5 tg, 25 Rg) were administered Fifteen healthy volunteers (nine men, six by bolus into the lumen of the jejunum. women, mean age 28 years, range 22-38) gave Cholera toxin reduced absorption of water and written informed consent to participate. None of electrolytes progressively over four hours and the subjects was taking any medication. A induced secretion in a dose dependent fashion. medical history, electrocardiograph, blood In the fourth hour net secretion amounted to 22 pressure, and standard laboratory findings were (23), 36 (24), and 88 (40) ml/30 cm/h (each obtained before the experiment and were found n=five) with doses of 6*25, 12-5, and 25 Fg to be negative or normal. Haematocrit was also cholera toxin, respectively. The movement of obtained 24 hours after the experiment. The sodium, chloride, and bicarbonate paralleled study was approved by the Ethics Committee of water movement. Our results suggest that the University of Graz School of Medicine. cholera toxin may serve as a secretory model in the human jejunum which might allow testing of new antisecretory agents. INTESTINAL PERFUSION (Gut 1992; 33: 1174-1178) For intestinal perfusion a tube assembly with a proximal occluding balloon was used.` The assembly with an outer diameter of 6 mm and a Secretory diarrhoea is an important health prob- mercury bag at the tip was placed in the jejunum lem particularly in developing countries. In (infusion site at the ligament of Treitz). The order to test new antisecretory agents human correct position of the tube was confirmed by models for intestinal secretion need to be estab- fluoroscopy. Because in animal studies digestive lished. Because infection with Vibrio cholerae is juices may destroy cholera toxin an occluding an important cause of diarrhoea, we decided to balloon proximal to the infusion site was used in use cholera toxin as intestinal secretagogue. order to avoid degradation of cholera toxin by Cholera toxin is the enterotoxin of Vibrio cholerae pancreatic enzymes9 (E Beubler, unpublished and while causing secretion does not impair observation). The sampling site was 30 cm distal glucose dependent sodium absorption in the to the infusion site. A fourth lumen enabled intestine and does not alter mucosal histology. I-3 removal of endogenous secretions proximal to Earlier studies with cholera toxin in man the occluding balloon. Perfusion was started in revealed an increase in stool frequency and the morning after a 12-16 hour fast. A plasma like electrolyte solution (composition in mmol/l: Na5 135, K+ 5, Cl- 110, HCO3- 30, and 2 g/l TABLE I Effect of various doses of cholera toxin (CT) on net polyethylene glycol, mean molecular weight jejunal water movement (ml/30 cmlh). Cholera toxin was 3350, as a non-absorbable volume marker) was administered as a bolus after two hours of control perfusion perfused at 10 ml/minute using a peristaltic Intrajejunal dose of CT pump. The solution was bubbled with a mixture Time (h) of 95% 02 and 5% CO2. A 30 minute equilibra25 'pg 6.25ptg 12.5 [tg after CT tion period, during which the samples were Control -54 (24) -118 (12) -135 (26) discarded was followed by six hours of collecControl -104 (12) -139 (19) -38 (22) -98 (1 1) -39 (21) -131 (22) 1 tion. Collection was performed by hand aspira2 - 120 (34)* -64 (12)* -37 (18) tion at a rate of 1.5 ml/minute using plastic 3 +4 (24)* +44 (49)* -17 (24) 4 +22 (23)*t +36 (24)*t +88 (40)*t syringes. Collected samples were pooled for each hour. After two control periods of one hour each, Quade test: *significantly different from controls, p
