NERVOUS CONTROL OF BLOOD PRESSURE

The control of blood pressure by the various reflexes of the cardiovascular
system has been extensively investigated in lower animals. The results
have been generalized to man. There is good evidence that many of the
reflexes that have been studied in lower animals are not the same in the
primate and therefore probably not applicable to man. The work which has
been done in man does not permit the isolation of the receptor systems and
therefore requires some assumptions to be made which may not be correct.
The objective of this research proposal is to examine the role of the
carotid, aortic and the cardiopulmonary receptors in the control of the
cardiovascular system in the primate. Since the study will involve the
conscious primate the results will not be clouded by the effects of
anesthetics. It will also address the question of the specificity of the
techniques of nonhypotensive hemorrhage and lower body negative and
positive pressure as selectively effecting cardiopulmonary receptors. In
order to more thoroughly address the question concerning the unloading of
cardiopulmonary receptors, aortic and carotid nerve recordings will be done
in the anesthetized monkey during nonhypotensive hemorrhages. After the
reflexes have been examined in the conscious primate the interaction of the
various reflexes will be studied. For sometime, it has been postulated
that alternations in the arterial baroreflex mechanisms could result in a
neurally mediated hypertension. This study will help to answer that
question and help us understand the possible involvement of these receptors
in pathologic conditions.