title: Effects of guinea pig neurotensin ([Ser7]neurotensin) on gastrointestinal smooth muscle.
abstract: Guinea pig neurotensin differs from other mammalian neurotensin by the substitution of proline by serine at position 7. [Ser7]neurotensin produced a concentration-dependent contraction of the guinea pig oesophagus and rat fundus, a biphasic effect (initial relaxation followed by more sustained contraction) on the guinea pig stomach corpus, duodenum and longitudinal muscle of the ileum and a relaxation of the guinea pig colon and rat ileum. The potencies (EC50) and % maximum contraction compared with the maximum effect produced by either histamine or acetylcholine of [Ser7]neurotensin and neurotensin were not significantly different in any tissue studied.
mesh_terms: D000818:Animals; D003106:Colon / Q000187:drug effects; D004386:Duodenum / Q000187:drug effects; D004947:Esophagus / Q000187:drug effects; D005748:Gastric Fundus / Q000187:drug effects; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D009496:Neurotensin / Q000031:analogs & derivatives* / Q000494:pharmacology; D051381:Rats; D013045:Species Specificity; D013270:Stomach / Q000187:drug effects
chemical_list: C049604:neurotensin, Ser(7)-; D009496:Neurotensin