Indexat a

Llicència i ús

Citacions

Cited 15 times in

Cited 15 times in

Cited 14 times in

Cited 37 times in

Altmetrics

Grant support

This work was supported by Ministerio de Ciencia e Innovacion Grant SAF 2007-60406 (to E. Vila) and Generalitat de Catalunya Grant 2009SGR-890. A. Marquez-Martin was supported by Universitat Autonoma de Barcelona.

Anàlisi d'autories institucional

Compartir

Middle cerebral artery alterations in a rat chronic hypoperfusion model

Publicat a:Journal Of Applied Physiology. 112 (3): 511-518 - 2012-02-01 112(3), DOI: 10.1152/japplphysiol.00998.2011

Autors: Marquez-Martin, Ana; Jimenez-Altayo, Francesc; Dantas, Ana P; Caracuel, Laura; Planas, Anna M; Vila, Elisabet

Afiliacions

Resum

Marquez-Martin A, Jimenez-Altayo F, Dantas AP, Caracuel L, Planas AM, Vila E. Middle cerebral artery alterations in a rat chronic hypoperfusion model. J Appl Physiol 112: 511-518, 2012. First published November 17, 2011; doi: 10.1152/japplphysiol.00998.2011.-Chronic cerebral hypoperfusion (CHP) induces microvascular changes that could contribute to the progression of vascular cognitive impairment and dementia in the aging brain. This study aimed to analyze the effects of CHP on structural, mechanical, and myogenic properties of the middle cerebral artery (MCA) after bilateral common carotid artery occlusion (BCCAO) in adult male Wistar rats. Sham animals underwent a similar surgical procedure without carotid artery (CA) ligation. After 15 days of occlusion, MCA and CA were dissected and MCA structural, mechanical, and myogenic properties were assessed by pressure myography. Collagen I/III expression was determined by immunofluorescence in MCA and CA and by Western blot in CA. mRNA levels for 1A1, 1A2, and 3A1 collagen subunits were quantified by quantitative real-time PCR in CA. Matrix metalloproteinase (MMP-1, MMP-2, MMP-9, and MMP-13) and hypoxia-inducible factor-1 alpha (HIF-1 alpha) protein expression were determined in CA by Western blot. BCCAO diminished cross-sectional area, wall thickness, and wall-to-lumen ratio. Nevertheless, whereas wall stress was increased, stiffness was not modified and myogenic response was diminished. Hypoperfusion triggered HIF-1 alpha expression. Collagen I/III protein expression diminished in MCA and CA after BCCAO, despite increased mRNA levels for 1A1 and 3A1 collagen subunits. Therefore, the reduced collagen expression might be due to proteolytic degradation, since the expression of MMP-1 and MMP-9 increased in the CA. These data suggest that BCCAO induces hypotrophic remodeling by a mechanism that involves a reduction of collagen I/III in association with increased MMP-1 and MMP-9 and that decreases myogenic tone in major arteries supplying the brain.

Paraules clau