title: Effect of bacterial lipopolysaccharide on gastric emptying of liquids in rats.
abstract: The objectives of the present investigation were 1) to study the effect of bacterial lipopolysaccharide (LPS) on rat gastric emptying (GE) and 2) to investigate a possible involvement of the vagus nerve in the gastric action of LPS. Endotoxin from E. coli (strain 055:B5) was administered sc, ip or iv to male Wistar rats (220-280 g body weight) at a maximum dose of 50 micrograms/kg animal weight. Control animals received an equivalent volume of sterile saline solution. At a given time period after LPS administration, GE was evaluated by measuring gastric retention 10 min after the orogastric infusion of a test meal (2 ml/100 g animal weight), which consisted of 0.9% NaCl plus the marker phenol red (6 mg/dl). One group of animals was subjected to bilateral subdiaphragmatic vagotomy or sham operation 15 days before the test. A significant delay in GE of the test meal was observed 5 h after iv administration of the endotoxin at the dose of 50 micrograms/kg animal weight. The LPS-induced delay of GE was detected as early as 30 min and up to 8 h after endotoxin administration. The use of different doses of LPS ranging from 5 to 50 micrograms/kg animal weight showed that the alteration of GE was dose dependent. In addition, vagotomized animals receiving LPS displayed a GE that was not significantly different from that of the sham control group. However, a participation of the vagus nerve in LPS-induced delay in GE could not be clearly demonstrated by these experiments since vagotomy itself induced changes in this gastric parameter. The present study provides a suitable model for identifying the mechanisms underlying the effects of LPS on gastric emptying.
authors.affiliation: Departamento de Pediatria and Núcleo de Medicina e Cirurgia Experimental, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, SP, Brasil.
authors.forename: E F
authors.initials: EF
authors.lastname: Collares
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000503:physiopathology*; D004926:Escherichia coli; D005746:Gastric Emptying / Q000502:physiology*; D008070:Lipopolysaccharides; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014628:Vagotomy
chemical_list: D008070:Lipopolysaccharides