Intracellular pH regulation in ferret ventricular muscle. The role of Na-H exchange and the influence of metabolic substrates.

Ferret ventricular muscle cells

Acid load via NH4Cl (10 or 20 mmol/l) with or without amiloride (0.75 or 1 mmol/l); intracellular sodium loading via strophanthidin; varying extracellular sodium and pH; changing metabolic substrate from glucose to pyruvate

Control conditions (e.g., glucose substrate, normal extracellular sodium and pH, absence of amiloride)

Intracellular pH (pHi) and intracellular sodium concentrationsurrogate