[Permanent endovascular occlusion of the middle cerebral artery in Wistar rats: a description of surgical approach through the internal carotid artery].
BACKGROUND
The importance of cerebral ischemia in clinical practice has driven the development of diverse experimental models of its different forms and different methods of producing it have been described. Here we report our experience with the use of the internal carotid artery (ICA) as an access route for the permanent endoluminal occlusion of the middle cerebral artery (MCA) in Wistar rats, and a detailed description of the procedure.


OBJECTIVE
Our aim at the at the Universidad de Cuenca Research Institute was to establish a standard technique for the constant and repeatable production of a focal cerebral infarct in the MCA territory in Wistar rats.


METHODS
Using a cervical approach, the ICA was dissected in 20 Wistar rats and, by means of an arteriotomy, a 25 mm long nylon 3-0 or 4-0 filament was introduced until the MCA was obstructed. The infracted area was delimited with 2,3,5-triphenyltetrazolium chloride and its volume was calculated using computer software.


RESULTS
Positive results were obtained in 10 cases, the mean volume of the infarct was 488.84 mm3, and the standard error was found to be 63.91 mm3. Subcortical infarcts occurred on three occasions. Two cases presented subarachnoid haemorrhage and two others showed parenchymatous haemorrhages; there were three deaths.


CONCLUSIONS
The use of the ICA as an entry point is an effective alternative for the endovascular production of focal cerebral ischemia and the use of a nylon 4-0 filament was more efficient than using a calibre 3-0 filament.
Peña-Tapia
P G
PG
Instituto de Investigaciones de la Universidad de Cuenca (IDIUC), Cuenca, Ecuador. pablog@medscape.com
Díaz
A H
AH
Torres
J L
JL
D000818:Animals; D002343:Carotid Artery, Internal / Q000601:surgery*; D002544:Cerebral Infarction; D004195:Disease Models, Animal; D005260:Female; D020244:Infarction, Middle Cerebral Artery; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013537:Sutures; D014656:Vascular Surgical Procedures / Q000379:methods*