Relation between non-bicarbonate buffer value and tolerance to cellular acidosis: a comparative study of myocardial tissue.

There is a large variation in the tolerance of myocardial tissue to cellular acidosis. Assuming the cytoplasmic acid-base status to be mainly a result of intracellular processes, this variation could be produced by variations in the tissue non-bicarbonate buffer value. In the myocardial tissue from nine vertebrate species, the non-bicarbonate buffer value did not correlate either with ability to develop tension under hypercapnic acidiosis or with the indirectly estimated capacity for anaerobic glycolysis. Therefore, differences in myocardial tolerance to acidosis must be explained either by an active pH regulation or by other compensatory mechanisms.