PERIPHERAL CENTRAL MECHANISMS OF BAROREFLEX RESETTING
- 28 June 1989
- journal article
- Published by Wiley in Clinical and Experimental Pharmacology and Physiology
- Vol. 16 (s15), 31-43
- https://doi.org/10.1111/j.1440-1681.1989.tb02994.x
Abstract
1 A change in the arterial pressure-sympathetic activity or heart rate relation (baroreflex resetting) can result from resetting of baroreceptors (‘peripheral’resetting) or from an altered coupling within the central nervous system of afferent baroreceptor to efferent nerve activities (‘central’resetting). 2.‘Peripheral’resetting involves a shift in the pressure-baroreceptor activity curve in the direction of the prevailing level of arterial pressure, e.g. after elevations in pressure, the baroreceptor pressure threshold (Pth) is increased and activity reduced at equivalent pressures and vascular strains. 3.‘Peripheral’resetting occurs during the diastolic phase of a cardiac cycle (instantaneous resetting), after brief exposure to elevated pressure (acute resetting), and during chronic hypertension or when chronic structural changes in the vasculature have occurred (chronic resetting). 4 Mechanisms include: (i) changes in the mechanical properties of the vessel wall that may alter the tension on the receptors; (ii) ionic mechanisms operating at the neuronal membrane such as activation of Na+, K+-ATPase; and (iii) release of endothelial factors that may modulate baroreceptor sensitivity. 5 Acute resetting of baroreceptors can be prevented or attenuated when the sustained elevations in pressure are pulsatile rather than static. Increases in flow increase carotid sinus nerve activity at constant pressure and strain and decrease the Pth of baroreceptors. 6.‘Central’resetting can involve neural-humoral interactions or an altered responsiveness of central neurons mediating the baroreflex to changes in afferent baroreceptor activity. 7 During static pressure, the continuous baroreceptor discharge causes significant‘central’resetting, i.e. sympathetic activity escapes from baroreflex inhibition. In contrast, during pulsatile pressure, the pulse phasic baroreceptor discharge minimizes‘central’resetting causing sustained sympathetic inhibition.Keywords
This publication has 29 references indexed in Scilit:
- Activated endothelial cells in culture suppress baroreceptors in the carotid sinus of dog.Hypertension, 1988
- Mechanisms of Resetting of Arterial Baroreceptors: An OverviewThe American Journal of the Medical Sciences, 1988
- Contrasting effects of static and pulsatile pressure on carotid baroreceptor activity in dogs.Circulation Research, 1987
- Prevention or attenuation of baroreceptor resetting by pulsatility during elevated pressure.Hypertension, 1987
- Prostacyclin production of the jsolated pulsatingly perfused rat aortaJournal of Pharmacological Methods, 1982
- Rapid resetting of the aortic baroreceptors in the rabbit and its implications for short-term and longer term reflex control.Circulation Research, 1982
- An electrogenic sodium pump and baroreceptor function in normotensive and spontaneously hypertensive rats.Circulation Research, 1976
- Thermal anomalies in ion distribution in rat kidney slices and in a model systemClinical and Experimental Pharmacology and Physiology, 1975
- Baroceptor Function in Chronic Renal HypertensionCirculation Research, 1956
- Afferent impulses in the carotid sinus nerve I. The relation of the discharge from single end organs to arterial blood pressureJournal of Cellular and Comparative Physiology, 1932