The effect of acidosis on the ECG of the rat heart

We have investigated the effect of acidosis on the ECG in isolated rat hear t to determine whether acidosis has marked effects on the ECG, and have use d pharmacological agents to investigate possible mechanisms whereby acidosi s alters the ECG. Acidosis produced a marked decrease in heart rate and an increase in P-R interval with little apparent effect on the duration of the QRS complex. The effects of acidosis did not appear to be due to acidosis- induced changes in transmitter release from severed autonomic nerve termina ls within the heart.