Premium
Aortic reactivity and electro‐physiology in normotensive rats, spontaneously hypertensive rats and rats made hypertensive with desoxycorticosterone plus salt
Author(s) -
Massingham R.,
Shevde S.
Publication year - 1971
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1971.tb07224.x
Subject(s) - medicine , endocrinology , spontaneously hypertensive rat , vascular smooth muscle , smooth muscle , blood pressure , aorta
The mechanical and electrophysiological activity of rings and strips of thoracic aortic smooth muscle taken from normotensive, DOCA-hypertensive and New Zealand spontaneously hypertensive (A.S. strain) rats have been compared. Aortae from A.S.-hypertensive rats developed less tension in the presence of noradrenaline and K+ than those isolated from normotensive and DOCA-hypertensive rats. Aortae from DOCA-hypertensive rats developed the same tension in response to K+ as normotensive rats but were less reactive to noradrenaline. Measurements of resting membrane potentials from the three groups of rats demonstrated that whereas normotensive and DOCA-hypertensive rats had similar resting membrane potentials, those from A.S.-hypertensive rats were significantly lower (P<0.001). It is suggested that the enhanced responsiveness of intact vascular beds in A.S.-hypertensive rats is a consequence of a change in the geometry of the blood vessels rather than an increase in the contractor response of the smooth muscle cells.