(Hypertension. 2000;35:1105.)
© 2000 American Heart Association, Inc.
Scientific Contributions |
From the Laboratoire de Pharmacologie Cardiovasculaire (O.R., J.A., C.C.-A., P.L., J.-M.C.), Faculté de Pharmacie, Nancy, France.
Correspondence to Jeffrey Atkinson, PhD, Laboratoire de Pharmacologie Cardiovasculaire, Faculté de Pharmacie, UHPNancy 1, 5, rue Albert Lebrun, BP 403, 54000 Nancy, France. E-mail atkinson{at}pharma.u-nancy.fr
AbstractStatins, which are often given to hypertensive patients, reduce the incidence of stroke. However, their effects on the cerebral circulation have been scarcely studied, although lovastatin has been reported to reduce hypertension-induced renal arteriolar hypertrophy. We examined the structure and mechanics of cerebral arterioles and the lower limit of cerebral blood flow (CBF) autoregulation in spontaneously hypertensive rats (SHR) that were untreated (n=9) or treated for 1 month with lovastatin (n=12; 20 mg · kg-1 · d-1) and in untreated Wistar-Kyoto rats (WKY; n=8). We studied the lower limit of CBF autoregulation by repeated measurement of CBF (arbitrary units; laser Doppler) and internal arteriolar diameter (µm; cranial window) at baseline and during stepwise hypotension. Stress-strain relationships were calculated from repeated measurement of internal arteriolar diameter during stepwise hypotension and cross-sectional area (CSA) of the vessel wall in maximally dilated cerebral arterioles (EDTA, 67 mmol/L). Lovastatin slightly reduced mean arterial pressure (treated, 153±3 versus untreated, 171±5 mm Hg, P<0.05; WKY, 106±3 mm Hg) and normalized CSA (treated, 826±52 versus untreated, 1099±16 µm2, P<0.05; WKY, 774±28 µm2). Stress-strain curves show that lovastatin also attenuated the increase in passive distensibility. Lovastatin had no effect on the external diameter of cerebral arterioles or the lower limit of CBF autoregulation. Our results show that although lovastatin has substantial effects on arteriolar mechanics and wall CSA, it has little effect on internal diameter. This phenomenon may explain its lack of effect on CBF autoregulation.
Key Words: hypertrophy remodeling inhibitors, HMG-CoA reductase autoregulation
This article has been cited by other articles:
![]() |
S. Delbosc, J.-P. Cristol, B. Descomps, A. Mimran, and B. Jover Simvastatin Prevents Angiotensin II-Induced Cardiac Alteration and Oxidative Stress Hypertension, August 1, 2002; 40(2): 142 - 147. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M Lefer, R. Scalia, and D. J Lefer Vascular effects of HMG CoA-reductase inhibitors (statins) unrelated to cholesterol lowering: new concepts for cardiovascular disease Cardiovasc Res, February 1, 2001; 49(2): 281 - 287. [Full Text] [PDF] |
||||
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2000 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |