Interactions between carotid sinus mechanoreceptor and chemoreceptor reflex loops
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Our experiments were designed to evaluate the combined influence of the mechanoreceptor and chemoreceptor control loops on the cardiovascular and respiratory systems. Both carotid sinus areas were isolated by a complete blind sac preparation in chloralose anesthetized dogs in which a flow probe had been implanted previously on the ascending aorta. The following variables were continuously monitored: central aortic pressure, heart rate, cardiac output, vascular resistance of a hind limb, tidal volume, respiratory rate, and oxygen consumption. While one sinus was submitted to step changes of pressure, the opposite sinus was kept at constant mean pressure. In addition, one sinus was perfused with either oxygenated of deoxygenated blood at constant flow rate.
These studies show a definite interaction between the control loops initiated by the carotid sinus mechanoreceptors and those initiated by the chemoreceptors. The influence of the chemoreceptors is most marked in the peripheral beds, where it shifts the whole response curve of the mechanoreceptor control loop upward. This response accounts for most of the upward shift of the pressure response curve.
On the other hand, the mechanoreceptor loop affects the ventilation, but this effect is range dependent, being most marked for the low pressure perfusion of the carotid sinus.
Key wordsDog Integrated control Cardiovascular and respiratory reflex interaction Minute ventilation Systemic arterial pressure Peripheral resistance
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- 1.Attinger, E. O., Attinger, F. M.: Hierarchy levels in the control of blood flow in the hind limb of the dog. Kybernetik13, 195–214 (1973)Google Scholar
- 2.Daly, M. De B., Hazzledine, J. L.: The effects of artificially induced hyperventilation on the primary cardiac reflex response to stimulation of the carotid bodies in the dog. J. Physiol. (Lond.)168, 872–889 (1963)Google Scholar
- 3.Daly, M. DeB., Hazzledine, J. L., Howe, A.: Reflex respiratory and peripheral vascular responses to stimulation of the isolated perfused aortic arch chemoreceptors of the dog. J. Physiol. (Lond.)177, 300–322 (1965)Google Scholar
- 4.Daly, M. DeB., Robinson, R. H.: An analysis of the reflex systemic vasodilator response elicited by lung inflation in the dog. J. Physiol. (Lond.)195, 387–406 (1968)Google Scholar
- 5.Daly, M. DeB., Scott, M. J.: The effects of stimulation of the carotid body chemoreceptors on the heart rate of the dog. J. Physiol. (Lond.)144, 148–166 (1958)Google Scholar
- 6.Daly, M. DeB., Scott, M. J.: The cardiovascular responses to stimulation of the carotid body chemoreceptors in the dog. J. Physiol. (Lond.)165, 179–197 (1963)Google Scholar
- 7.Daly, M. DeB., Scott, M. J.: The cardiovascular effects of hypoxia in the dog with special reference to the contribution of the carotid body chemoreceptors. J. Physiol. (Lond.)173, 201–214 (1964)Google Scholar
- 8.Hornbein, T. F.: The relationship between stimulus to chemoreceptors and their response. In: Wates Symposium on Arterial Chemoreceptors (R. W. Torrance, ed.), pp. 65–76. Oxford: Blackwell 1968Google Scholar
- 9.Kenner, T., Ueda, M., Huntsman, L., Attinger, E. O.: Effect of local and general hypoxia on iliac flow. Angiologica5, 345–363 (1968)Google Scholar
- 10.Korner, P. I., Uther, J. B., White, S. W.: Central nervous integration of the circulatory and respiratory responses to arterial hypoxia in the rabbit. Circulat. Res.24, 757–776 (1969)Google Scholar
- 11.Pearce, D. H.: A system for measuring oxygen consumption and control of inspired carbon dioxide. IEEE Trans. BME18, 235–237 (1971)Google Scholar
- 12.Peterson, L. H., Feigl, E. O., Gouras, P.: Properties of the carotid sinus mechanism. Fed. Proc.19, 40 (Abstract) (1960)Google Scholar
- 13.Spickler, W. J., Kezdi, P.: Dynamic response characteristics of the carotid sinus baroreceptors. Amer. J. Physiol.212, 474 (1967)Google Scholar