Back to Search
Start Over
Pathological role of a constitutively active population of alpha(1D)-adrenoceptors in arteries of spontaneously hypertensive rats.
- Source :
-
British journal of pharmacology [Br J Pharmacol] 2002 Jan; Vol. 135 (1), pp. 206-16. - Publication Year :
- 2002
-
Abstract
- 1. The role of a constitutively active population of alpha(1D)-adrenoceptors was analysed in arteries obtained from spontaneously hypertensive rats (SHR) and controls (WKY) divided into three groups: young prehypertensive, adult hypertensive, and adult animals chronically treated with captopril (50 mg kg(-1) per day orally) in order to prevent the hypertensive state. 2. In adult SHR, a significant increase in BMY 7378 potency (not in prazosin potency) was observed in aorta, mesenteric artery, and the first and second branches of the small mesenteric arteries with respect to WKY rats. This difference was not observed in iliac and tail arteries, which suggests an increased functional role of alpha(1D)-adrenoceptors only in some vessels of SHR. 3. The increase in the resting tone (IRT) observed in absence of agonist, inhibited by BMY 7378, that represents the constitutively active population of alpha(1D)-adrenoceptors, was also significantly greater in aorta and mesenteric artery from adult SHR. 4. In young and captopril treated adult animals, no differences between strains with respect to BMY 7378 potency, or IRT were observed. 5. The increase in the functional role of alpha(1D)-adrenoceptors and their constitutive activity observed in hypertension is prevented by captopril treatment. The pathological consequence of this change is the slower rate of recovery of the basal tone after removal of an adrenergic stimulus, observed in vessels from hypertensive animals that had shown an increase in the functionality of constitutively active alpha(1D)-adrenoceptors. This change was not observed in prehypertensive or captopril treated animals.
- Subjects :
- Adrenergic alpha-Agonists pharmacology
Adrenergic alpha-Antagonists pharmacology
Age Factors
Animals
Antihypertensive Agents pharmacology
Aorta, Thoracic drug effects
Aorta, Thoracic physiopathology
Arteries drug effects
Captopril pharmacology
Dose-Response Relationship, Drug
Hemodynamics drug effects
Iliac Artery drug effects
Iliac Artery physiopathology
In Vitro Techniques
Male
Mesenteric Arteries drug effects
Mesenteric Arteries physiopathology
Muscle Contraction drug effects
Muscle Contraction physiology
Muscle Relaxation drug effects
Muscle Relaxation physiology
Muscle, Smooth, Vascular physiology
Norepinephrine pharmacology
Phenylephrine pharmacology
Piperazines pharmacology
Prazosin pharmacology
Rats
Rats, Inbred SHR
Rats, Inbred WKY
Receptors, Adrenergic, alpha-1 drug effects
Tail blood supply
Vasoconstriction drug effects
Vasodilation drug effects
Arteries physiopathology
Hypertension physiopathology
Receptors, Adrenergic, alpha-1 physiology
Subjects
Details
- Language :
- English
- ISSN :
- 0007-1188
- Volume :
- 135
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- British journal of pharmacology
- Publication Type :
- Academic Journal
- Accession number :
- 11786496
- Full Text :
- https://doi.org/10.1038/sj.bjp.0704447