Summary
During hypoxia cardiac contraction declines and there is an intracellular acidosis. We find that, if this acidosis is abolished by decreasing pCO2 there is little restoration of force. Therefore the acidosis is not the major cause of the decline of force. The acidosis may partly result from the generation of lactic acid. No acidosis, is however, seen in isolated cardiac cells. Furthermore a theoretical model shows that lactic acid production would be expected to produce a transient acidosis. We suggest that the observed maintained acidosis may be a consequence of extracellular lactic acid accumulation affecting intracellular pH.
Similar content being viewed by others
References
Allen DG, Eisner DA, Morris PG, Pirolo JS, Smith GL (1986) Metabolic consequences of increasing intracellular calcium and force production in perfused ferret hearts. Journal of Physiology 376:121–141
Allen DG, Morris PG, Orchard CH, Pirolo JS (1985) A nuclear magnetic resonance study of metabolism in the ferret heart during hypoxia and inhibition of glycolysis. Journal of Physiology 361:185–204
Allen DG, Orchard CH (1983) The effects of changes of pH on intracellular calcium transients in mammalian cardiac muscle. Journal of Physiology 335:555–567
Bauer C, Donoso P, Eisner DA, Smith GL (1989) The effects of metabolic blockade on intracellular pH in isolated ferret hearts. Journal of Physiology 415:105P
Bountra C, Kaila K, Vaughan Jones RD (1988) Mechanism of rate-dependent pH changes in the sheep cardiac Purkinje fibre. Journal of Physiology 406:483–501
Dennis SC, Gevers W, Opie LH (1991) Protons in ischaemia: where do they come from; where do they go to? Journal of Molecular and Cellular Cardiology 23:1077–1086
Donoso P, Mill JG, O'Neill SC, Eisner DA (1992) Fluorescence measurements of cytoplasmic and mitochondrial sodium concentration in rat ventricular myocytes. J Physiol 448:493–509
Eisner DA, Elliott AC, Smith GL (1987) The contribution of intracellular acidosis to the decline of developed pressure in ferret hearts exposed to cyanide. Journal of Physiology 391:99–108
Eisner DA, Nichols CG, O'Neill SC, Smith GL, Valdeolmillos M (1989) The effects of metabolic inhibition on intracellular calcium and pH in isolated rat ventricular cells. Journal of Physiology 411:393–418
Fabiato A, Fabiato F (1978) Effects of pH on the myofilaments and the sarcoplasmic reticulum of skinned cells from cardiac and skeletal muscles. Journal of Physiology 276:233–255
Kentish JC (1986) The effects of inorganic phosphate and creatine phosphate on force production in skinned muscles from rat ventricle. Journal of Physiology 370:585–604
Poole RC, Halestrap AP (1993) Transport of lactate and other monocarboxylates across mammalian plasma membranes. American Journal of Physiology 264:C761-C782
Strupp M, Kammermeier H (1993) Interstitial lactate and glucose concentrations of the isolated perfused rat heart before, during and after anoxia. Pflügers Archiv European Journal of Physiology 423:232–237
Wang X, Poole RC, Halestrap AP, Levi AJ (1993) Characterization of the inhibition by stilbene disulphonates and phloretin of lactate and pyruvate transport into rat and guinea-pig cardiac myocytes suggests the presence of two kinetically distinct carriers in heart cells. Biochemical Journal 290:249–258
Wilkie DR (1979) Generation of protons by metabolic processes other than glycolysis in muscle cells. Journal of Molecular and Cellular Cardiology 11:325–330
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Eisner, D.A., Smith, G.L. & O'Neill, S.C. The effects of lactic acid production on contraction and intracellular pH during hypoxia in cardiac muscle. Basic Res Cardiol 88, 421–429 (1993). https://doi.org/10.1007/BF00795409
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00795409