Journal of Advances in Medicine and Medical Research, ISSN: 2456-8899, ISSN: 2231-0614 (Past),Vol.: 26, Issue.: 2
Reduction in Jejunal Fluid Absorption In vivo through Distension and Cholinergic Stimulation Not Attributable to Enterocyte Secretion
M. L. Lucas1*, H. L. Kenward1, P. C. Watson1, S. R. Sabir1, C. J. R. Turkington1, P. Tainsh1, S. McColl1, V. S. Graham1 and E. McNaughton1 1Laboratory of Gastrointestinal Physiology, School of Life Sciences, College of Medicine, Veterinary Medicine & Life Sciences, Glasgow University, Glasgow G12 8QQ, Scotland, Great Britain, UK.
M. L. Lucas1*, H. L. Kenward1, P. C. Watson1, S. R. Sabir1, C. J. R. Turkington1, P. Tainsh1, S. McColl1, V. S. Graham1 and E. McNaughton1
1Laboratory of Gastrointestinal Physiology, School of Life Sciences, College of Medicine, Veterinary Medicine & Life Sciences, Glasgow University, Glasgow G12 8QQ, Scotland, Great Britain, UK.
(1) Ige, Serah Funke, Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Ogbomoso, Nigeria.
(2) Panagiotis Korovessis, Department of Orthopaedic, Chief Orthopaedic Surgeon, General Hospital “Agios Andreas” Patras, Greece.
(1) Tolga Dinc, Ankara Numune Training Hospital, Turkey.
(2) Nitin Gupta, Max Superspeciality Hospital, India.
(3) Ketan Vagholkar, D. Y. Patil University School of Medicine, India.
Complete Peer review History: http://www.sciencedomain.org/review-history/24134
Jejunal fluid absorption in vivo was reduced by distension and by hydrostatic pressure and further declined on adding E. coli STa enterotoxin but no net fluid secretion was detected. Luminal atropine reduced pressure mediated reductions in fluid absorption to normal values but intravenous hexamethonium was without effect. A neural component to inhibition of absorption by pressure (though not stretch) may be mediated by axon reflexes within cholinergic neurons.Perfusion of cholinergic compounds also reduced net fluid absorption but did not cause secretion. In order to show that these actions were not secretory processes stimulated by cholinergic compounds that offset normal rates of absorption, these compounds were tested for their ability to cause net secretion in loops that were perfused with solutions in which choline substituted for sodium ion. In addition, these perfusates additionally contained E. coli STa enterotoxin or EIPA (ethyl-isopropyl-amiloride) to minimize absorption.In these circumstances, where it might be expected to do so if it were acting through a secretory rather than an absorptive mechanism, carbachol did not cause net fluid secretion. Cholinergic stimulation and pressure induced distension are thought to reduce net fluid absorption through inducing secretion but are found only to reduce fluid absorption.In conclusion, distension and cholinergic stimulation of the small intestine are two further circumstances in which fluid secretion is assumed to explain their action on fluid movement, as required by the enterocyte secretion model of secretion but, which like STa enterotoxin, instead are only able to reduce fluid absorption. This casts further doubt on the widespread validity of the enterocyte secretion model for fluid appearance in the lumen in diarrhoeal diseases.
Intestine; secretion; diarrhea; intestinal stretch; E. coli STa; enterotoxin; enterocyte.
DOI : 10.9734/JAMMR/2018/39184Review History Comments