Relation between the aortic pressure and the cardiac cycle in different neurovegetative conditions in the conscious
A Federici1, G Sorrentino, R Sambati
1Institute of Human Physiology, University of Bari, Italy.
Abstract:
The relation between mean aortic pressure (mAoP) and the duration of cardiac cycle (C) has been studied in resting conscious dogs in normal condition (n), after vagal blockade (vb), after sympathetic blockade (sb), and after combined blockade of the two systems (sb+vb). The relation has been found to be negative in all conditions. The different conditions are clearly differentiated by the slope of the relation between mAoP/C (= kPa/s = mW/ml) and C. The hypothesis is put forward that the balance between sympathetic and parasympathetic activities on the heart and the vessels produces the best compromise between the pump function of the heart and the afterload, in relation to the actual behavioural situation, in conscious animals.
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