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Effects of celiprolol on reflex control of the cardiovascular system in essential hypertension
Insights
Celiprolol, a beta blocker with vasodilator properties, maintains essential neural control of circulation in hypertensive patients. This antihypertensive drug preserves baroreceptor and cardiopulmonary reflex functions, enhancing circulatory homeostasis.
Area of Science:
- Cardiovascular Physiology
- Pharmacology
- Hypertension Research
Background:
- Beta-blockers like acebutolol and nadolol generally preserve neural control of circulation.
- Celiprolol possesses both beta-blocking and vasodilator properties, potentially impacting neural cardiovascular control.
Purpose of the Study:
- To investigate the effects of celiprolol on reflex control of circulation in essential hypertension.
- To determine if celiprolol's vasodilator action interferes with neural cardiovascular regulation.
Main Methods:
- Measurements of blood pressure, heart rate, central venous pressure, and forearm blood flow/resistance.
- Assessment of arterial baroreceptor and cardiopulmonary receptor activity using lower body suction and passive leg raising.
- Study conducted before and after 5-7 days of oral celiprolol administration (200-400 mg/day) in six hypertensive subjects.
Main Results:
- Celiprolol reduced blood pressure and increased forearm blood flow, indicating vasodilatation.
- Heart rate responses to baroreceptor manipulation remained unchanged.
- Celiprolol reset the carotid baroreflex, increasing its tonic restraint on blood pressure despite hypotension.
- The inhibitory restraint from cardiopulmonary receptors on peripheral circulation was also enhanced.
Conclusions:
- Celiprolol preserves fundamental neural mechanisms of circulatory homeostasis in hypertensive patients.
- The drug enhances tonic neural restraint on blood pressure and peripheral circulation.
- Celiprolol's vasodilating effects do not impair, but rather augment, key cardiovascular reflexes.
Abstract:
We have previously shown that baroreceptor control of the cardiovascular system and the cardiopulmonary receptor control of peripheral circulation are preserved or only moderately reduced during antihypertensive treatment with acebutolol or nadolol, which indicates that treatment with beta blockers with or without intrinsic sympathomimetic activity does not impair fundamental neural mechanisms involved in circulatory homeostasis. In the present study we have investigated the reflex control of circulation before and during antihypertensive treatment with celiprolol, which, in addition to its beta-blocking action, has vasodilator properties that may stem from interference with neural cardiovascular control. In six essential hypertensive subjects we measured blood pressure (intraarterial catheter), heart rate (ECG recording), central venous pressure (right atrial catheter), and forearm blood flow and resistance (plethysmography) before and during alterations in the activity of the arterial baroreceptors obtained by means of lower body suction and passive leg raising. The study was performed before and after 5-7 days of oral administration of celiprolol at 200-400 mg once a day. Compared to the values obtained in the control, condition celiprolol caused a reduction in blood pressure, a slight change in heart rate, and an increase in forearm blood flow, which indicated the occurrence of a clear-cut forearm vasodilatation. The heart rate responses to arterial baroreceptor manipulation were unchanged by celiprolol which reset the carotid baroreflex so that its tonic restraint on blood pressure increased despite the hypotension induced by the drug. The inhibitory restraint tonically exerted by the cardiopulmonary receptors on peripheral circulation was also increased by celiprolol.(ABSTRACT TRUNCATED AT 250 WORDS)