Middle cerebral artery occlusion in rats: a neurological and pathological evaluation of a reproducible model

Neurosurgery. 1992 Jul;31(1):100-6; discussion 106-7. doi: 10.1227/00006123-199207000-00014.


Middle cerebral artery occlusion (MCAO) in rats produces an infarct of varying size. We examined three factors that may influence this variability: animal weight, vascular anatomy, and extent of occlusion in rats undergoing MCAO. We also developed a four-point neurological evaluation scale and validated its usefulness by comparing it with a four-grade pathological determination of the size of the infarct. Of 82 animals subjected to a standard MCAO, 34 developed small cortical infarcts (pathological grades I-II; infarct size less than 25 mm2, 6-17% of the ipsilateral cortex surface area), and 48 large infarcts (pathological grades III-IV, infarct size greater than 25 mm2, 20-56% of surface area). We were able to predict the size of infarction from the neurological evaluation in 83% of the animals, and this accuracy reached 91% when grades I and II and III and IV were considered together (P less than 0.001). In 41 animals subjected to a more extensive vascular occlusion, 89% exhibited large infarcts. Four vascular patterns were identified but none played a significant role in the incidence or size of the cortical stroke. However, rats weighing less than 300 g showed a smaller lesion size than did rats greater than 300 g. Our proposed new MCAO technique appears useful in reproducing large-sized infarcts of the frontoparietal cortex.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Behavior, Animal / physiology*
  • Brain / pathology
  • Brain / physiopathology
  • Brain Ischemia / pathology
  • Brain Ischemia / physiopathology
  • Brain Mapping
  • Cerebral Arteries / pathology
  • Cerebral Arteries / physiopathology
  • Cerebral Cortex / blood supply
  • Cerebral Cortex / pathology
  • Cerebral Cortex / physiopathology
  • Cerebral Infarction / pathology
  • Cerebral Infarction / physiopathology*
  • Collateral Circulation / physiology
  • Disease Models, Animal*
  • Dominance, Cerebral / physiology
  • Male
  • Motor Skills / physiology
  • Neurologic Examination
  • Rats
  • Rats, Inbred Strains
  • Regional Blood Flow / physiology
  • Stereotyped Behavior / physiology