Abstract
Force-frequency relations in the isolated papillary muscles of rats and guinea-pigs were compared using isometric force measurement technique. Stimulation frequency varied between 0.33 and 4 Hz. Under normal conditions the rat papillary muscle exhibits a negative force-frequency dependence which differs from ventricular preparations in many other mammals. Caffeine (10 mmol/l) introduced into the bath solution abolishes a negative force-frequency dependence in the papillary muscle of rat. During incubation of the rat ventricular preparations in the caffeine-containing solution the force-frequency relations measured on these muscles display the same behaviour as in guinea pig preparations. Caffeine has induced no changes in the force-frequency relations of guinea-pig ventricular preparations. A conclusion is made that caffeine-sensitive intracellular calcium stores participate in species-determined differences in force-frequency relations of the ventricular muscles.
Translated title of the contribution | Effect of caffeine on chronotropic correlations in the myocardium of the rat and guinea pig |
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Original language | Russian |
Pages (from-to) | 97-100 |
Number of pages | 4 |
Journal | Fiziologicheskii Zhurnal |
Volume | 39 |
Issue number | 4 |
Publication status | Published - Jul 1993 |
Externally published | Yes |
ASJC Scopus subject areas
- Physiology