Hypoxia-Ischemia Induced Nigrostriatal System Damages and Motor Behavioral Changes in Neonatal Rat Brain. |
Kim, Se Won , Kim, Seung Beom , Lee, Su Young , Kim, Jong Moon , Lim, Jeong Hoon , Lee, In Sik , Lee, Jongmin , Koh, Seong Eun |
Department of Rehabilitation Medicine, Konkuk University School of Medicine, Korea. kohse@kuh.ac.kr |
신생쥐에서 저산소성 허혈성 뇌손상 후 흑색질-선조체 및 운동행위 손상 |
김세원, 김승범, 이수영, 김종문, 임정훈, 이인식, 이종민, 고성은 |
건국대학교 의학전문대학원 재활의학교실 |
|
|
|
Abstract |
Objective To investigate hypoxia-ischemia induced nigrostriatal system damages and motor behavioral changes in the immature developing rat brain. Method For establishment of hypoxia-ischemia (HI) injury, bilateral common carotid artery occlusion was performed permanently with bipolar electrocoagulation in the postnatal day 5 rats. And then rat pups were immediately subjected to hypoxic exposure (8% oxygen) at 37oC for 1 hour. The control group underwent sham operation and normoxic exposure. Brain injury including striatonigral system was examined. Motor behavioral changes were investigated at 2-, 4-, 6- and 8-week after HI injury using the Rota-rod test and the d-amphetamine-induced locomotor activity. Results HI-induced motor behavioral deficits showed from 2-week to 8-week after HI injury. In the Rota-rod test, HI group exhibited significantly shorter mean fall latencies as compared to the control group. The d-amphetamine-induced locomotor activity test at the same time point showed reduced locomotor activity in HI group. HI injury resulted in brain structural damages in hippocampus, dorsolateral region of striatum and substantia nigra, and decreases in tyrosine hydroxylase-positive dopaminergic neurons in the substantia nigra. There was no evidence of spontaneous recovery in the substantia nigra at the 8-week after injury. Conclusion HI induced brain injury at neonatal period could result in persistent motor behavioral deficits in juvenile rats. Those deficits might be linked with structural damages including nigrostriatal dopaminergic system. (J Korean Acad Rehab Med 2009; 33: 649-656) |
Key Words:
Hypoxia-ischemia, Brain injury, Motor behavior, Tyrosine hydroxylase |
|