Journal article
Structure of Cerebral Arterioles in Mice Deficient in Expression of the Gene for Endothelial Nitric Oxide Synthase
Circulation research, Vol.95(8), pp.822-829
10/15/2004
DOI: 10.1161/01.RES.0000146279.11923.14
PMID: 15388643
Abstract
We examined effects of pharmacological inhibition of nitric oxide synthase (NOS) and genetic deficiency of the endothelial isoform of NOS (eNOS) on structure and mechanics of cerebral arterioles. We measured pressure, diameter, and cross-sectional area (CSA) of the vessel wall (histologically) in maximally dilated cerebral arterioles in mice that were untreated or treated for 3 months with the NOS inhibitor, N-nitro-l-arginine methyl ester (l-NAME; 10 mg/kg per day in drinking water). Treatment with l-NAME increased systemic arterial mean pressure (SAP; 143±4 versus 121±4 mm Hg, P<0.05) and CSA (437±27 versus 310±34 μm, P<0.05). These findings suggest that hypertension induced in mice by NOS inhibition is accompanied by hypertrophy of cerebral arterioles. To determine the role of the eNOS isoform in regulation of cerebral vascular growth, we examined mice with targeted disruption of one (heterozygous) or both (homozygous) genes encoding eNOS. Wild-type littermates served as controls. SAP and CSA were significantly increased in homozygous (SAP, 141±5 versus 122±3 mm Hg in wild-type mice, P<0.05; CSA, 410±18 versus 306±15 μm in wild-type mice, P<0.05), but not in heterozygous (SAP, 135±4 mm Hg; CSA, 316±32 μm) eNOS-deficient mice. Carotid ligation normalized cerebral arteriolar pulse pressure did not prevent increases in CSA in homozygous eNOS-deficient mice. Thus, cerebral arterioles undergo hypertrophy in homozygous eNOS-deficient mice, even in the absence of increases in arteriolar pulse pressure. These findings suggest that eNOS plays a major role in regulation of cerebral vascular growth.
Details
- Title: Subtitle
- Structure of Cerebral Arterioles in Mice Deficient in Expression of the Gene for Endothelial Nitric Oxide Synthase
- Creators
- Gary Baumbach - From the Departments of Pathology (G.L.B.) and Internal Medicine (C.D.S., F.M.F.), University of Iowa College of Medicine & Cardiovascular Center, Iowa City, IowaCurt SigmundFrank Faraci
- Resource Type
- Journal article
- Publication Details
- Circulation research, Vol.95(8), pp.822-829
- DOI
- 10.1161/01.RES.0000146279.11923.14
- PMID
- 15388643
- NLM abbreviation
- Circ Res
- ISSN
- 0009-7330
- eISSN
- 1524-4571
- Publisher
- American Heart Association, Inc
- Language
- English
- Date published
- 10/15/2004
- Academic Unit
- Molecular Physiology and Biophysics; Pathology; Cardiovascular Medicine; Fraternal Order of Eagles Diabetes Research Center; Neuroscience and Pharmacology; Internal Medicine
- Record Identifier
- 9984040370802771
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