Ondansetron reduces nausea induced by gastroduodenal stimulation without changing gastric motility. Feinle, Christine, and Nicholas W. Read. Centre for Human Nutrition, The University of Sheffield, Northern General Hospital, Sheffield, U. K.
APStracts 3:0087G, 1996.
The involvement of 5-HT3 receptors in the gastric motor and sensory responses to distension and duodenal lipid was investigated. Subjects were studied on four occasions, during which isotonic saline or 20 % Intralipid (2 kcal/ml) was infused intraduodenally (1 ml/min), while the proximal stomach was distended with air (100 ml/min). The subjects received either 8 mg ondansetron (5-HT3 antagonist) or placebo orally in random order. Intragastric pressure was recorded continuously and the subjects reported gastric sensations. Gastric motor and sensory responses to distension during duodenal saline were similar with placebo and ondansetron. Intraduodenal lipid decreased gastric tonic and phasic pressure activity, and this was not influenced by ondansetron. Lipid also induced meal-like fullness followed by nausea during distensions. Ondansetron reduced nausea, did not affect meal-like fullness, but increased volumes and pressures at which the sensations were reported. Intestinal 5-HT3 receptors are involved in the induction of nausea, but not of meal -like fullness by intraduodenal lipid and gastric distension. 5-HT3 receptor antagonism reduces gastric sensitivity to distension during intraduodenal lipid infusion. 

Received 6 July 1995; accepted in final form 25 March 1996.
APS Manuscript Number G284-5.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 8 May 96