The role of Ca2plus in the contractility of rabbit small intestine in vitro

• Autorzy: Grasa L. , Rebollar E. , Arruebo M.P. , Plaza M.A. , Murillo M.D.
• Języki publikacji: EN

Abstrakty

EN

This study evaluated the role of Ca2+ in spontaneous and ACh- and KCl-induced contractions in longitudinal and circular smooth muscle from rabbit small intestine in vitro. In the first experiment, the amplitude, frequency and tone of spontaneous contractions in longitudinal and circular smooth muscle of small intestine were determined and, in the second experiment, the ACh- and KCl-induced responses of longitudinal and circular smooth muscle were measured. Atropine and guanethidine reduced the amplitude and tone of contractions in longitudinal and circular muscle, but reduced the frequency of contractions in circular muscle, only. TTX attenuated the amplitude of contractions and decreased the tone of contractions in longitudinal muscle, but increased the tone in circular muscle. Ca2+-free solutions, verapamil, nifedipine and caffeine diminished the three parameters of spontaneous contractions. Thapsigargin and cyclopiazonic acid increased the amplitude and tone of contractions in ileum longitudinal muscle, only, and cyclopiazonic acid increased the amplitude of contractions in circular muscle. Ca2+-free solutions, verapamil, nifedipine, thapsigargin, cyclopiazonic acid, and caffeine diminished ACh- and KCl-induced contractions. Those results suggest that extracellular Ca2+ plays a role in spontaneous contractions, and extracellular and intracellular Ca2+ participate in the ACh- and KCl-induced contractions of rabbit small intestine.

Słowa kluczowe

EN

spontaneous contraction; small intestine; circular muscle; jejunum; longitudinal muscle; duodenum; in vitro; ileum; rabbit

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 2004
• Tom: 55
• Numer: 3
• Opis fizyczny: p.639-650,fig.,ref.

Twórcy

autor

Grasa L.

• Universidad de Zaragoza, Miguel Servet 177. 50013 Zaragoza, Spain

autor

Rebollar E.

autor

Arruebo M.P.

autor

Plaza M.A.

autor

Murillo M.D.