AJP - Heart and Circulatory Physiology, Vol 240, Issue 4 555-H560, Copyright © 1981 by American Physiological Society
Inhibition of carotid pressor response by left aortic depressor nerve in dogs
S. C. Walgenbach, D. E. Donald and A. Melcher
In 12 conscious dogs, the mean increase of 26 mmHg in arterial pressure
during carotid occlusion was augmented by 52 mmHg after section of the left
cervical vagus nerve and 6 mmHg after right vagal section. In 18
anesthetized dogs, in which the cervical vagal nerves were reversibly cold
blocked, corresponding values were 33, 28, and 6 mmHg, respectively. In
nine of these dogs, this left-sided dominance was present after bilateral
section of the vagal cardiopulmonary afferents; it was absent after
bilateral section of the aortic nerves in the other nine dogs. In five dogs
on cardiopulmonary bypass with heart and lungs excluded, pressure within
the isolated aorta and major intrathoracic arteries was raised from 120 to
220 mmHg. The resultant hypotension reflexly induced by activation of
aortic baroreceptors was reduced by left but not by right vagal cold block.
It was concluded that, in the dog, the left aortic nerve provided the major
inhibition of the increase in arterial pressure after carotid occlusion.
