Please use this identifier to cite or link to this item:
Title: Effect of acidosis and alkalosis on postischemic Ca gain in isolated rat heart.
Austin Authors: Panagiotopoulos, Sianna ;Daly, Mark J;Nayler, W G
Affiliation: Department of Medicine, University of Melbourne, Austin Hospital, Heidelberg, Victoria, Australia
Issue Date: 1-Mar-1990
Publication information: The American Journal of Physiology; 258(3 Pt 2): H821-8
Abstract: The effect of pH of the reperfusion buffer on postischemic changes in tissue Ca and Na was examined in isolated Langendorff-perfused Sprague-Dawley rat hearts. Reperfusion began after 15-, 25-, or 60-min ischemia at 37 degrees C. After 60-min ischemia, reperfusion at pH 6.4 or 6.6 attenuated the reperfusion-induced Ca gain so long as the acidotic conditions were maintained (3.08 +/- 0.22, 1.37 +/- 0.41, and 16.96 +/- 1.18 mumol Ca gain/g dry wt for pH 6.4, 6.6, and 7.4, respectively after 15-min reperfusion). Conversely, reperfusion under alkalotic conditions (pH 7.9) after 60-min ischemia exacerbated the gain (27.45 +/- 4.75 and 8.92 +/- 1.53 mumol Ca gain/g dry wt during 5-min reperfusion at pH 7.9 and 7.4, respectively). Similar, but less pronounced Ca gains occurred during reperfusion after 15- or 25-min ischemia. Sodium content during reperfusion, but not during aerobic perfusion, was also found to be pH sensitive with acidosis causing a reduction and alkalosis an increase. These results could not be explained in terms of an effect of pH on recovery of high-energy phosphates, percentage "reflow" during reperfusion, or reperfusion-induced increases in tissue water or resting tension. The results are in agreement with the hypothesis that the "inhibitory" effect of acidosis on postischemic Ca overload could involve an effect of pH on the Na(+)-H+ exchanger and intracellular Ca storage.
Gov't Doc #: 2316696
ORCID: 0000-0002-0845-0001
Journal: American Journal of Physiology
Type: Journal Article
Subjects: Acidosis.metabolism
Acidosis, Respiratory.metabolism
Adenosine Triphosphate.metabolism
Alkalosis, Respiratory.metabolism
Biomechanical Phenomena
Coronary Disease.metabolism.physiopathology
Hydrogen-Ion Concentration
In Vitro Techniques
Mitochondria, Heart.metabolism
Myocardial Reperfusion
Rats, Inbred Strains
Time Factors
Appears in Collections:Journal articles

Show full item record

Page view(s)

checked on Jan 26, 2023

Google ScholarTM


Items in AHRO are protected by copyright, with all rights reserved, unless otherwise indicated.