CIRCULATORY RESPONSES TO SELECTIVE ACTIVATION OF MYELINATED AND UNMYELINATED FIBERS OF THE AORTIC NERVE

In experiments on thoracotomized cats the arterial blood pressure (BP), cardiac frequency, force of contraction of a fragment of the left ventricle, and the resistance of the blood vessels of the hind limb were recorded. Myelinated and unmyelinated fibers (A and C fibers) of the left aortic nerve were stimulated selectively. Lowering of BP in response to stimulation of A fibers was observed to take place mainly through a decrease in the peripheral vascular resistance, whereas during excitation of C fibers the cardiac component of the reflex - a reduction in the frequency and force of cardiac contractions - was most marked. © 1980 Plenum Publishing Corporation.