Brain research. Developmental brain research
-
Brain Res. Dev. Brain Res. · Jun 1997
Influence of age on the cerebral lesions in an immature rat model of cerebral hypoxia-ischemia: a light microscopic study.
The most frequently used model of neonatal cerebral hypoxia-ischemia consists of a 7-day postnatal rat model with combined common carotid artery ligation and hypoxemia. Neuropathologic studies have shown major differences between this 7-day postnatal rat model and a similar adult model in regard to overall cerebral vulnerability, type and distribution of lesions. It is not clear how and when during animals' development these changes in cerebral vulnerability take place. ⋯ During the first 5 postnatal days relative vulnerability of hippocampal regions is similar, but as the animals' development proceeds and hippocampal vulnerability increases lesions tend to involve specific regions while sparing others. By age 13 postnatal days CA1 and lateral CA3 develop increased vulnerability while medial CA3 and fascia dentata become relatively resistant and by 21 postnatal days adult pattern of CA1 selective vulnerability is approached. The underlying mechanisms for these changes in regional vulnerability to cerebral hypoxia-ischemia during development should be sought in complex regional anatomic, functional, and metabolic alterations that take place as brain matures.