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Updated: May 23, 2026

Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues
Published on: June 3, 2019
α-adrenoceptor blocking drugs, pressor responses to noradrenaline, and the ankle jerk in man
1Department of Clinical Pharmacology, St Bartholomew's Hospital, London.
Abstract:
1 Changes in pressor responses to infused noradrenaline and in triceps surae jerk amplitude have been measured after the i.v. administration of: chlorpromazine, thioridazine, prochlorperazine, dimethothiazine, indoramin, benzoctamine and clonidine. 2 Each of the drugs blocked pressor responses to noradrenaline and reduced triceps surae jerk amplitude, but little correlation was found between their potencies in the two systems. 3 The effects of the drugs on the triceps surae jerk are not incompatible with an action at a spinal α-adrenoceptor site, but other pharmacological factors may be involved, such as penetration of the drugs into the central nervous system, and differences in their uptake(1) blocking activity.
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