baroreceptor reflex การใช้

• The Bainbridge reflex and the baroreceptor reflex control heart rate.
• Some research suggests the existence of intracranial baroreceptors to trigger specific Cushing baroreceptor reflex.
• The cardiac centers monitor baroreceptor firing to maintain cardiac homeostasis, a mechanism called the baroreceptor reflex.
• The baroreceptor reflex can correct for a change in arterial pressure by increasing or decreasing heart rate.
• Generally, the baroreceptor reflex is not targeted in hypertension because if blocked, individuals may suffer from orthostatic hypotension and fainting.
• The main limiting side-effects of alpha antagonists is that the baroreceptor reflex is disrupted and thus this can cause postural hypotension.
• However, because dihydropyridine CCBs result in a decrease in blood pressure, the baroreceptor reflex often initiates a reflexive increase in sympathetic activity leading to increased heart rate and contractility.
• Angiotensin II increases thirst sensation ( dipsogen ) through the subfornical organ of the brain, decreases the response of the baroreceptor reflex, and increases the desire for sympathetic fibers.
• If blood pressure falls, such as on orthostatic hypotension or in hypovolaemic shock, baroreceptor firing rate decreases and baroreceptor reflexes act to help restore blood pressure by increasing heart rate.
• Since moment-to-moment blood pressure regulation is carried out by the sympathetic nervous system ( via the baroreceptor reflex ), calcium channel blockers allow blood pressure to be maintained more effectively than do beta blockers.
• The objective would be to elicit the baroreceptor reflex as the receptors detect an apparent high pressure state due to the externally applied force and causes reflex bradycardia and / or hypotension, leading to decreased blood supply to the brain and syncope.
• Still, the blood pressure does not normally fall very much, because it immediately triggers a vasoconstriction ( baroreceptor reflex ), pressing the blood up into the body again . ( Often, this mechanism is exaggerated and is why diastolic blood pressure is a bit higher when a person is standing up, compared to a person in the horizontal position . ) Therefore, a secondary factor that causes a greater than normal fall in blood pressure is often required.