title: Effect of nitric oxide on propagated clusters of spontaneous motor waves in an ex vivo rabbit intestinal preparation.
abstract: The aim of this study was to determine whether nitric oxide can play a role in regulating the propagation of spontaneous motor activity in a rabbit intestinal preparation completely excluded from any central and vascular connection. Experiments were done on nine rabbits of either sex, weighing 2.5 +/- 0.5 kg (mean +/- SD). After one week of semiliquid diet the animals were sacrificed and a segment including the stomach, duodenum and part of the jejunum was removed and placed into a single chamber organ bath containing 1 L of oxygenated Krebs' solution. Four strain gauges connected to a Dynograph Recorder were sutured on the serosal surface 10 cm apart starting from the gastric antrum to the distal duodenum. Once the motor activity was stabilized, N-nitro-L-arginine methyl-ester (L-NAME) was added to the bath at increasing concentration from 10(-7) to 10(-4) M. Spontaneous motor activity was recorded, characterized by the cycling occurrence of bursts of waves, starting from the stomach and propagating to the descending duodenum. L-NAME at higher concentrations reduced the time interval between the bursts of waves with a concomitant increase in the propagation velocity of the motor activity. No change in the frequency of waves was detected. The effect of L-NAME was prevented by the administration of L-Arginine. This study suggests an important role for the nitric oxide pathway in the distal propagation of the spontaneous motor activity of the alimentary tract.
authors.affiliation: University G. D'Annunzio, School of Gastroenterology, Casa di Cura Pierangeli, Pescara, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Grossi
authors.forename: M
authors.initials: M
authors.lastname: Falcucci
authors.forename: D
authors.initials: D
authors.lastname: Lapenna
authors.forename: L
authors.initials: L
authors.lastname: Marzio
mesh_terms: D000818:Animals; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D007583:Jejunum / Q000187:drug effects / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D009569:Nitric Oxide / Q000502:physiology*; D011817:Rabbits; D013270:Stomach / Q000187:drug effects / Q000502:physiology
chemical_list: D009569:Nitric Oxide; D019331:NG-Nitroarginine Methyl Ester