Baroreceptors


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Baroreceptors

 

(baroceptors, mechanoreceptors, and pressoreceptors), sensory nerve terminals in blood vessels that perceive changes in blood pressure and reflexly regulate its level. Baroreceptors become stimulated when the walls of the vessels distend. They are found in all vessels but are concentrated mainly in reflexogenic zones (such as cardiac, aortic, carotid sinus, and pulmonary). When blood pressure rises, baroreceptors send impulses to the central nervous system that decrease the tonus of the vascular center and excite the central formations of the parasympathetic division of the autonomic nervous system, and result in a lowering of the pressure. After a frequent and prolonged rise in blood pressure, the baroreceptors adapt to it and thereby may be one of the causes of hypertension.

G. N. KASSIL’

References in periodicals archive ?
Contribution of baroreceptors and chemoreceptors to ventricular hypertrophy produced by sino-aortic denervation in rats.
Larger blood volume and stroke volume in athletes also maintain higher activation of arterial baroreceptors leading to increased parasympathetic activation (Boushel et al.
For example, pressure on the carotid baroreceptors from balloon dilation or stent deployment commonly causes sudden bradycardia or transient asystole.
This will be detected by baroreceptors that stimulate sympathetic nervous responses to maintain circulation, and the renin-angiotensin-aldosterone system (RAAS).
In this position increased central blood volume via arterial baroreceptors imposes a greater vagal activation than in the supine position and reduces heart rate and cardiac output (Rowell, 1993).
As P waves come earlier and sinus rhythm returns, the appropriately timed atrial systole and the synchronous ventricular contraction resulting from normal depolarization produce an increase in stroke volume that causes the baroreceptors to increase parasympathetic tone and decrease sympathetic tone.
Baroreceptors (pressure-sensitive receptors found in major vessels such as the aorta) trigger sympathetic activation when blood pressure is decreased and triggers or sympathetic deactivation when blood pressure is increased.
Two afferent pathways, one from baroreceptors and one from osmoreceptors, control the secretion of AVP in the presence of hypovolemia or hyperosmolality.
The system works by electrically activating baroreceptors, the body's natural blood pressure sensors that regulate cardiovascular function.
Baroreceptors are stretch receptors found in the aorta and internal carotid arteries that monitor mean arterial pressure.
Changes in blood pressure are signalled to the brain by nerve cells called baroreceptors.
In doing this, the baroreceptors, part of the blood pressure regulatory mechanism, send messages to the brain stem, which instigates peripheral vasodilation and hypotension as a compensatory mechanism.