Effect of sodium butyric acid, sodium valerianic acid, and osmolarity on contractility of specimens of intestinal wall obtained from the cecum and spiral colon of healthy cows.

Objective: To compare the effect of various concentrations of sodium butyric acid and sodium valerianic acid, as well as various osmolarities, on contractility of ex-vivo intestinal wall specimens obtained from the cecum and spiral colon of each of several healthy cows.

Sample Population: Full-thickness preparations of intestinal wall, dissected parallel to the longitudinal smooth muscle layers, harvested from freshly slaughtered healthy cows.

Procedure: Specimens of intestinal wall were incubated for 5 minutes with various concentrations of sodium butyric acid and sodium valerianic acid as well as various osmolar concentrations of NaCl, using a crossover design. Isometric contractions were induced 7 times with carbachol (CH; 5 X 10(-6) mol/L). Contractility was defined as the maximum amplitude of contraction and the amplitude of contraction 2 minutes after addition of CH.

Results: Repeated addition of CH did not result in a significant effect on contractility of specimens from the cecum and spiral colon. Contractility after addition of CH was not significantly affected by prior incubation with various concentrations of sodium butyric acid or sodium valerianic acid or after an increase of osmolarity. Maximum amplitude of contraction was significantly higher in specimens from the spiral colon, compared with specimens from the cecum.

Conclusions: Increases in concentrations of sodium butyric acid or sodium valerianic acid and increases in osmolarity did not inhibit contractility of intestinal wall specimens from the cecum and spiral colon of a group of healthy cows.