AJP - Gastrointestinal and Liver Physiology, Vol 245, Issue 4 562-G567, Copyright © 1983 by American Physiological Society

ARTICLES

Methylprednisolone increases absorptive capacity of rabbit ileum in vitro

J. H. Sellin and R. C. DeSoignie

The effect of glucocorticoids on intestinal ion transport was studied in ileum in vitro from control and methylprednisolone (MP)-treated (40 mg im for 2 days) rabbits under the following conditions: a) basal rates of Na and Cl transport, b) the response to an individual absorptive stimulus (alanine, glucose, or epinephrine), and c) the response to a combination of the three absorptive stimuli. The results indicate that MP 1) increases basal absorption of Na and Cl and secretion of bicarbonate (as measured by residual ion flux), 2) does not alter the specific transport pathways stimulated by maximal doses of alanine, glucose, or epinephrine, but 3) significantly increases the absorptive capacity of ileum. After addition of combined alanine, glucose, and epinephrine, MP-treated ileum absorbed 15.8 mueq X cm-2 X h-1 Na (vs. 6.6 in controls, P less than 0.001) and 9.5 mueq X cm-2 X h-1 Cl (vs. 4.1 in controls, P less than 0.005). Additionally MP did not alter the Na dependence of either the short-circuit current or Cl absorption found in controls, although there appears to be a portion of residual ion flux insensitive to epinephrine inhibition. These data suggest that the MP-induced increase in absorptive capacity is due to an increase in a postapical transport step, most probably the Na pump.

This article has been cited by other articles:

				S. Coon and U. Sundaram Mechanism of glucocorticoid-mediated reversal of inhibition of Cl-/HCO-3 exchange during chronic ileitis Am J Physiol Gastrointest Liver Physiol, April 1, 2000; 278(4): G570 - G577. [Abstract] [Full Text] [PDF]