Elevated vascular reactivity in the timolol-treated spontaneously hypertensive rat

M. T. Goldberg, Christopher Triggle

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Spontaneously hypertensive rats (SHR) treated in utero with a low dose, and from weaning with 6 mg/kg/day of oral timolol, a noncardioselective β-adrenergic blocker, did not develop hypertension. Isolated aortic rings from these animals showed increased reactivity to raised extracellular K+, when compared with tissues from timolol-treated Kyoto-Wistar (WKY) control rats. The normotensive SHR aorta also showed significant responsiveness to H+ and to high Ca2+ concentrations without previously depolarizing the tissue with high K+. These observations suggest that the increased reactivity seen in vascular smooth muscle from this animal does not develop secondary to elevated peripheral resistance and subsequent hypertrophy, and that the initiation of hypertension in this animal may be related to a membrane defect and/or cellular defect which results in a facilitation of Ca2+ availability for the contractile proteins of the SHR vascular smooth muscle cell.

Original languageEnglish
Pages (from-to)1072-1075
Number of pages4
JournalCanadian Journal of Physiology and Pharmacology
Volume56
Issue number6
Publication statusPublished - 1978
Externally publishedYes

Fingerprint

Timolol
Inbred SHR Rats
Blood Vessels
Vascular Smooth Muscle
Hypertension
Contractile Proteins
Adrenergic Antagonists
Inbred WKY Rats
Weaning
Vascular Resistance
Hypertrophy
Smooth Muscle Myocytes
Aorta
Membranes

ASJC Scopus subject areas

  • Physiology
  • Pharmacology

Cite this

Elevated vascular reactivity in the timolol-treated spontaneously hypertensive rat. / Goldberg, M. T.; Triggle, Christopher.

In: Canadian Journal of Physiology and Pharmacology, Vol. 56, No. 6, 1978, p. 1072-1075.

Research output: Contribution to journalArticle

@article{1edc399357cf4fcdbf4791e0e3cb042e,
title = "Elevated vascular reactivity in the timolol-treated spontaneously hypertensive rat",
abstract = "Spontaneously hypertensive rats (SHR) treated in utero with a low dose, and from weaning with 6 mg/kg/day of oral timolol, a noncardioselective β-adrenergic blocker, did not develop hypertension. Isolated aortic rings from these animals showed increased reactivity to raised extracellular K+, when compared with tissues from timolol-treated Kyoto-Wistar (WKY) control rats. The normotensive SHR aorta also showed significant responsiveness to H+ and to high Ca2+ concentrations without previously depolarizing the tissue with high K+. These observations suggest that the increased reactivity seen in vascular smooth muscle from this animal does not develop secondary to elevated peripheral resistance and subsequent hypertrophy, and that the initiation of hypertension in this animal may be related to a membrane defect and/or cellular defect which results in a facilitation of Ca2+ availability for the contractile proteins of the SHR vascular smooth muscle cell.",
author = "Goldberg, {M. T.} and Christopher Triggle",
year = "1978",
language = "English",
volume = "56",
pages = "1072--1075",
journal = "Canadian Journal of Physiology and Pharmacology",
issn = "0008-4212",
publisher = "National Research Council of Canada",
number = "6",

}

TY - JOUR

T1 - Elevated vascular reactivity in the timolol-treated spontaneously hypertensive rat

AU - Goldberg, M. T.

AU - Triggle, Christopher

PY - 1978

Y1 - 1978

N2 - Spontaneously hypertensive rats (SHR) treated in utero with a low dose, and from weaning with 6 mg/kg/day of oral timolol, a noncardioselective β-adrenergic blocker, did not develop hypertension. Isolated aortic rings from these animals showed increased reactivity to raised extracellular K+, when compared with tissues from timolol-treated Kyoto-Wistar (WKY) control rats. The normotensive SHR aorta also showed significant responsiveness to H+ and to high Ca2+ concentrations without previously depolarizing the tissue with high K+. These observations suggest that the increased reactivity seen in vascular smooth muscle from this animal does not develop secondary to elevated peripheral resistance and subsequent hypertrophy, and that the initiation of hypertension in this animal may be related to a membrane defect and/or cellular defect which results in a facilitation of Ca2+ availability for the contractile proteins of the SHR vascular smooth muscle cell.

AB - Spontaneously hypertensive rats (SHR) treated in utero with a low dose, and from weaning with 6 mg/kg/day of oral timolol, a noncardioselective β-adrenergic blocker, did not develop hypertension. Isolated aortic rings from these animals showed increased reactivity to raised extracellular K+, when compared with tissues from timolol-treated Kyoto-Wistar (WKY) control rats. The normotensive SHR aorta also showed significant responsiveness to H+ and to high Ca2+ concentrations without previously depolarizing the tissue with high K+. These observations suggest that the increased reactivity seen in vascular smooth muscle from this animal does not develop secondary to elevated peripheral resistance and subsequent hypertrophy, and that the initiation of hypertension in this animal may be related to a membrane defect and/or cellular defect which results in a facilitation of Ca2+ availability for the contractile proteins of the SHR vascular smooth muscle cell.

UR - http://www.scopus.com/inward/record.url?scp=0018220755&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018220755&partnerID=8YFLogxK

M3 - Article

C2 - 743625

AN - SCOPUS:0018220755

VL - 56

SP - 1072

EP - 1075

JO - Canadian Journal of Physiology and Pharmacology

JF - Canadian Journal of Physiology and Pharmacology

SN - 0008-4212

IS - 6

ER -