|
|
||||||||
AJP - Gastrointestinal and Liver Physiology, Vol 249, Issue 1 39-G47, Copyright © 1985 by American Physiological Society
ARTICLES |
J. D. Wagner, P. Kurtin and A. N. Charney
We have previously reported that changes in colonic net Na and Cl absorption correlate with arterial CO2 partial pressure (PCO2) and that changes in colonic net Cl absorption and HCO3 secretion correlate with the plasma HCO3 concentration during the systemic acid-base disorders. To determine whether changes in intracellular pH (pHi) and HCO3 concentration [( HCO3]i) mediate these effects, we measured pHi and calculated [HCO3] in the distal colonic mucosa of anesthetized, mechanically ventilated Sprague-Dawley rats using 5,5-[14C]dimethyloxazolidine-2,4-dione and [3H]inulin. Rats were studied during normocapnia, acute respiratory acidosis and alkalosis, and uncompensated and pH-compensated acute metabolic acidosis and alkalosis. When animals in all groups were considered, there were strong correlations between mucosal pHi and both arterial PCO2 (r = -0.76) and pH (r = 0.82) and between mucosal [HCO3]i and both arterial PCO2 (r = 0.98) and HCO3 concentration (r = 0.77). When we considered the rates of colonic electrolyte transport that characterized these acid-base disorders [A. N. Charney and L. P. Haskell. Am. J. Physiol. 246 (Gastrointest. Liver Physiol. 9): G159-G165, 1984], we found strong correlations between mucosal pHi and net Na absorption (r = -0.86) and between mucosal [HCO3]i and both net Cl absorption (r = 0.98) and net HCO3 secretion (r = 0.83). These findings suggest that the systemic acid-base disorders cause changes in colonic mucosal pHi and [HCO3]i as a consequence of altered arterial PCO2 and HCO3 concentration. In addition, the effects of these disorders on colonic electrolyte transport may be mediated by changes in mucosal pHi and [HCO3]i.
This article has been cited by other articles:
![]() |
A. N. Charney, R. W. Egnor, D. Henner, H. Rashid, N. Cassai, and G. S. Sidhu Acid-base effects on intestinal Cl- absorption and vesicular trafficking Am J Physiol Cell Physiol, May 1, 2004; 286(5): C1062 - C1070. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |