| Full text | |
| Author(s): |
Leoni, Renata F.
;
Paiva, Fernando F.
;
Kang, Byeong-Teck
;
Henning, Erica C.
;
Nascimento, George C.
;
Tannus, Alberto
;
de Araujo, Draulio B.
;
Silva, Afonso C.
Total Authors: 8
|
| Document type: | Journal article |
| Source: | TRANSLATIONAL STROKE RESEARCH; v. 3, n. 1, p. 12-pg., 2012-03-01. |
| Abstract | |
Collateral circulation, defined as the supplementary vascular network that maintains cerebral blood flow (CBF) when the main vessels fail, constitutes one important defense mechanism of the brain against ischemic stroke. In the present study, continuous arterial spin labeling (CASL) was used to quantify CBF and obtain perfusion territory maps of the major cerebral arteries in spontaneously hypertensive rats (SHRs) and their normotensive Wistar-Kyoto (WKY) controls. Results show that both WKY and SHR have complementary, yet significantly asymmetric perfusion territories. Right or left dominances were observed in territories of the anterior (ACA), middle and posterior cerebral arteries, and the thalamic artery. Magnetic resonance angiography showed that some of the asymmetries were correlated with variations of the ACA. The leptomeningeal circulation perfusing the outer layers of the cortex was observed as well. Significant and permanent changes in perfusion territories were obtained after temporary occlusion of the right middle cerebral artery in both SHR and WKY, regardless of their particular dominance. However, animals with right dominance presented a larger volume change of the left perfusion territory (23 +/- 9%) than animals with left dominance (7 +/- 5%, P<0.002). The data suggest that animals with contralesional dominance primarily safeguard local CBF values with small changes in contralesional perfusion territory, while animals with ipsilesional dominance show a reversal of dominance and a substantial increase in contralesional perfusion territory. These findings show the usefulness of CASL to probe the collateral circulation. (AU) | |
| FAPESP's process: | 06/05706-5 - Evaluation of hemodynamic response in patients with carotid stenosis under hypercapnia |
| Grantee: | Renata Ferranti Leoni |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 05/56663-1 - Magnetic resonance imaging and in vivo spectroscopy center for animal model studies |
| Grantee: | Alberto Tannús |
| Support Opportunities: | Inter-institutional Cooperation in Support of Brain Research (CINAPCE) - Thematic Grants |