Sensitivity and adrenoceptor affinity in the mesenteric artery of the deoxycorticosterone acetate hypertensive rat

P. A. Perry, R Clinton Webb

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

This study examines vascular reactivity to α-adrenoceptor agonists in mineralocorticoid (deoxycorticosterone acetate (DOCA-salt)) hypertensive and normotensive rats. The rats were anesthetized and the mesenteric artery was excised and cut helically into strips that were mounted in a muscle bath for the measurement of isometric force development. Addition of norepinephrine, epinephrine, phenylephrine, methoxamine, or clonidine to the bath contractions in all arteries. Arteries from hypertensive rats were more sensitive (lower ED50 values) to each of the agonists than arteries from normotensive rats. α-Adrenoceptor affinity for phentolamine (Schild analysis; norepinephrine as the agonist) in hypertensive arteries was not significantly different from that in normotensive arteries. Maximal force generation to clonidine was greater in hypertensive arteries than in normotensive arteries. These results demonstrate an augmented vascular sensitivity to several α-adrenoceptor agonists in DOCA hypertensive rats. This change in sensitivity is independent of a change in affinity for the adrenoceptor antagonist, phentolamine. It may be that a change in receptor number or an alteration in a post-receptor activation event accounts for this enhanced adrenoceptor responsiveness in mineralocorticoid hypertension.

Original languageEnglish (US)
Pages (from-to)1095-1099
Number of pages5
JournalCanadian Journal of Physiology and Pharmacology
Volume66
Issue number8
DOIs
StatePublished - Jan 1 1988
Externally publishedYes

Fingerprint

Desoxycorticosterone
Mesenteric Arteries
Adrenergic Receptors
Acetates
Arteries
Desoxycorticosterone Acetate
Mineralocorticoids
Phentolamine
Clonidine
Baths
Blood Vessels
Norepinephrine
Methoxamine
Phenylephrine
Epinephrine
Salts
Hypertension
Muscles

ASJC Scopus subject areas

  • Physiology
  • Pharmacology
  • Physiology (medical)

Cite this

@article{17add4aa48cb4459b631870e5549f827,
title = "Sensitivity and adrenoceptor affinity in the mesenteric artery of the deoxycorticosterone acetate hypertensive rat",
abstract = "This study examines vascular reactivity to α-adrenoceptor agonists in mineralocorticoid (deoxycorticosterone acetate (DOCA-salt)) hypertensive and normotensive rats. The rats were anesthetized and the mesenteric artery was excised and cut helically into strips that were mounted in a muscle bath for the measurement of isometric force development. Addition of norepinephrine, epinephrine, phenylephrine, methoxamine, or clonidine to the bath contractions in all arteries. Arteries from hypertensive rats were more sensitive (lower ED50 values) to each of the agonists than arteries from normotensive rats. α-Adrenoceptor affinity for phentolamine (Schild analysis; norepinephrine as the agonist) in hypertensive arteries was not significantly different from that in normotensive arteries. Maximal force generation to clonidine was greater in hypertensive arteries than in normotensive arteries. These results demonstrate an augmented vascular sensitivity to several α-adrenoceptor agonists in DOCA hypertensive rats. This change in sensitivity is independent of a change in affinity for the adrenoceptor antagonist, phentolamine. It may be that a change in receptor number or an alteration in a post-receptor activation event accounts for this enhanced adrenoceptor responsiveness in mineralocorticoid hypertension.",
author = "Perry, {P. A.} and Webb, {R Clinton}",
year = "1988",
month = "1",
day = "1",
doi = "10.1139/y88-179",
language = "English (US)",
volume = "66",
pages = "1095--1099",
journal = "Canadian Journal of Physiology and Pharmacology",
issn = "0008-4212",
publisher = "National Research Council of Canada",
number = "8",

}

TY - JOUR

T1 - Sensitivity and adrenoceptor affinity in the mesenteric artery of the deoxycorticosterone acetate hypertensive rat

AU - Perry, P. A.

AU - Webb, R Clinton

PY - 1988/1/1

Y1 - 1988/1/1

N2 - This study examines vascular reactivity to α-adrenoceptor agonists in mineralocorticoid (deoxycorticosterone acetate (DOCA-salt)) hypertensive and normotensive rats. The rats were anesthetized and the mesenteric artery was excised and cut helically into strips that were mounted in a muscle bath for the measurement of isometric force development. Addition of norepinephrine, epinephrine, phenylephrine, methoxamine, or clonidine to the bath contractions in all arteries. Arteries from hypertensive rats were more sensitive (lower ED50 values) to each of the agonists than arteries from normotensive rats. α-Adrenoceptor affinity for phentolamine (Schild analysis; norepinephrine as the agonist) in hypertensive arteries was not significantly different from that in normotensive arteries. Maximal force generation to clonidine was greater in hypertensive arteries than in normotensive arteries. These results demonstrate an augmented vascular sensitivity to several α-adrenoceptor agonists in DOCA hypertensive rats. This change in sensitivity is independent of a change in affinity for the adrenoceptor antagonist, phentolamine. It may be that a change in receptor number or an alteration in a post-receptor activation event accounts for this enhanced adrenoceptor responsiveness in mineralocorticoid hypertension.

AB - This study examines vascular reactivity to α-adrenoceptor agonists in mineralocorticoid (deoxycorticosterone acetate (DOCA-salt)) hypertensive and normotensive rats. The rats were anesthetized and the mesenteric artery was excised and cut helically into strips that were mounted in a muscle bath for the measurement of isometric force development. Addition of norepinephrine, epinephrine, phenylephrine, methoxamine, or clonidine to the bath contractions in all arteries. Arteries from hypertensive rats were more sensitive (lower ED50 values) to each of the agonists than arteries from normotensive rats. α-Adrenoceptor affinity for phentolamine (Schild analysis; norepinephrine as the agonist) in hypertensive arteries was not significantly different from that in normotensive arteries. Maximal force generation to clonidine was greater in hypertensive arteries than in normotensive arteries. These results demonstrate an augmented vascular sensitivity to several α-adrenoceptor agonists in DOCA hypertensive rats. This change in sensitivity is independent of a change in affinity for the adrenoceptor antagonist, phentolamine. It may be that a change in receptor number or an alteration in a post-receptor activation event accounts for this enhanced adrenoceptor responsiveness in mineralocorticoid hypertension.

UR - http://www.scopus.com/inward/record.url?scp=0023749379&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023749379&partnerID=8YFLogxK

U2 - 10.1139/y88-179

DO - 10.1139/y88-179

M3 - Article

C2 - 2902915

AN - SCOPUS:0023749379

VL - 66

SP - 1095

EP - 1099

JO - Canadian Journal of Physiology and Pharmacology

JF - Canadian Journal of Physiology and Pharmacology

SN - 0008-4212

IS - 8

ER -