Mechanical Restitution in Left and Right Guinea Pig Ventricular Preparations
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چکیده
The present study was focused on identification of possible differences in the onset and time course of mechanical restitution in guinea pig multicellular heart preparations, i.e., papillary muscles from the right and left ventricles. Stimulated twitches of both preparations mounted in a horizontal perfusion bath were recorded simultaneously. Mechanical restitution curves were constructed at 25°C and 35°C and at stimulation rates of 0.5 Hz, 1 Hz and 2 Hz. No statistically significant differences in restitution curves of both preparations were found. It can be concluded that, in the assessment of mechanical behaviour of the heart, the guinea pig left ventricular papillary muscle appears to be a suitable substitute for the conventionally employed right ventricular papillary muscles.
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