Abstract
The effect of acid base alterations was analyzed using isolated rat hearts perfused at constant coronary perfusion pressure, and stimulated to contract at constant rate. The amount of shortening in the major axis and its derivative were measured to assess myocardial contractility. Both the 'respiratory' and 'metabolic' alterations affected the contractile behavior to the same extent. In the physiological range studied by us, acidosis depresses and alkalosis increases myocardial contraction. However, acidosis seems to depress contractility more than the enhancement produced by the same change in pH towards the alkalotic side. When either amount of shortening or max dl/dt was plotted as a function of hydrogen ion activity ((a)H+) a linear correlation was obtained, either with pure 'metabolic' or 'respiratory' acid base induced alterations (correlation coefficients higher than -.95; P < .01). The authors' findings suggest that in the range studied, contraction of the perfused rat heart following acid base alterations, is a linear function of hydrogen ion activity.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 329-336 |
| Number of pages | 8 |
| Journal | European Journal of Cardiology |
| Volume | 3 |
| Issue number | 4 |
| State | Published - 1975 |
| Externally published | Yes |
ASJC Scopus subject areas
- General Medicine