Peripheral determination of the vascular effect of the carotid depressor reflex

Experiments were carried out to study the changes in the vascular muscle contraction and the vascular bed resistance of cat hind leg in response to identical activation of the sinocarotid baroreceptors, however with different initial functional state of the vascular bed. Determining the dilatatory responses of the vascular bed in a state of rest, of increased tissue osmolarity and upon increase in femoral blood flow without the presence of autoregulatory reaction, it was shown that the baroreceptor decrease of the vascular contraction is peripherally conditioned by the value of the initial contraction, while the baroreceptor decrease of the resistance is determined by the ratio between the initial contraction and the initial radius. The peripheral determination of the organ differentiation of the depressor effect of the carotid baroreceptor reflex is discussed on the basis of these results.