Role of Tissue-Type Plasminogen Activator in Neonatal Rat with Hypoxia-Ischemia Brain Damage / 实用儿科临床杂志

ABSTRACT

Objective To explore the role of tissue-type plasminogen activator(tPA) in neonatal rat with hypoxia-ischemia brain damage(HIBD).Methods Seven-day-old Wistar rat pups were used for the Vannucci model of HIBD.Reverse transcription-polymerase chain reaction(RT-PCR),terminal deoxynucleotidyl transferase mediated dUTP nick end labeling(TUNEL),double immunostaining and immunoblot analysis were adapted to determin the expression of tPA at acute phase after HIBD and neural cell apoptosis and the blood-brain-barrier(BBB) damage.Results Neonatal hypoxia-ischemia triggers persistent induction of the plasminogen system.The increase of tPA activity induced the degradation of laminin and occludin which would aggravate the BBB damage.The number of neural cell apoptosis after HIBD increased progressively with the reperfusion time.Conclusions The increase of tPA at the acute phase after HIBD can help clot to dissolve,while its extravascular proteolysis will induce cell apoptosis and BBB damage which will aggravate brain injury.