Microvascular structure after embolic focal cerebral ischemia in the rat.
OBJECTIVE
We analyze morphological alterations of cerebral neovascularization after stroke using a new 3D imaging software program.


METHODS
Male Wistar rats underwent unilateral embolic middle cerebral artery occlusion (MCAo) by a single fibrin rich clot. Subjects were sacrificed from 1 to 28 days post infarct. Vessel perimeters were measured on coronal sections stained with endothelial cell-specific antibody to von Willebrand's factor. Vessel segment lengths, diameters and number of vessels were analyzed on cerebral microvessels perfused with FITC-dextran 14 days after ischemia using LSCM and a 3-D vessel quantification program.


RESULTS
The mean number of microvessels with enlarged perimeters significantly increased in the ipsilateral cortex at day 7 when compared to the contralateral cortex (29.7+/-14.7 vs. 3.7+/-2.5, P<0.05). Subsequently, differences in the number of microvessels with enlarged perimeters decreased on days 14 and 28. Fourteen days post-MCA occlusion, microvessel segment length (15.0 vs. 26.0 microm, P<0.05) and diameter (3.14 vs. 3.75 microm, P<0.05) significantly decreased in the ipsilateral hemisphere when compared to the contralateral hemisphere, respectively. Furthermore, the mean total number of these smaller microvessels increased in the ipsilateral hemisphere (57.33+/-14.5 vs. 32.22+/-11.7, P<0.05).


CONCLUSIONS
Focal cerebral ischemia induces morphological changes (early dilated microvessels followed by decreased microvessel segment length and diameter) that are consistent with newly generated microvessels.
Morris
Daniel C
DC
Departments of Emergency Medicine, Henry Ford Health System, 2799 West Grand Blvd., Detroit, MI 48202, USA.
Yeich
Thomas
T
Khalighi
Mohammad Mehdi
MM
Soltanian-Zadeh
Hamid
H
Zhang
Zheng G
ZG
Chopp
Michael
M
D000818:Animals; D002545:Brain Ischemia / Q000473:pathology* / Q000503:physiopathology; D002540:Cerebral Cortex / Q000473:pathology*; D004195:Disease Models, Animal; D007839:Functional Laterality; D021621:Imaging, Three-Dimensional / Q000379:methods; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology*; D008297:Male; D008833:Microcirculation / Q000473:pathology*; D018919:Neovascularization, Physiologic; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors