The Study On Protective Effect And Its Mechanism Of K_ATP Channel Opener On Hypoxic-Ischemic Brain Damage In Neonatal Rats

Objective To investigate the protective effect and mechanism of the ATP-sensitive potassium channel opener (KCO) cromakalim on hypoxic-ischemic brain damage (HIBD) in neonatal rats.Methods 150 neonatal rats (7 days after birth) were randomly divided into 5 groups: control group, sham operation group, HIBD group, cromakalim affected group(KCO group) and cromakalim plus glibenclamide(K_ATP channel inhibitor, KCI) affected group(KCO plus KCI group).Setting up HIBD model: The left common carotid artery of rats were ligated firstly and then the rats were put into the hypoxic cabin with the mixed gases of N₂ and O₂ for 2.5 hours. There were no any operation to the normal group. The rats in sham operation group were cut the skin of neck without ligating the left common carotid artery. The concentration of O₂ which was kept between 7%-9% on average in hypoxic cabin was monitored by oxygen meter.All the rats were killed 72 hours after the establishment of the HIBD model. The pathologic changes, neural cell apoptosis, and the expression of Bcl-2 and Bax were observed through the techniques of HE staining, TUNEL staining and immunohistochemical staining. The content of SOD and MDA of brain were detected...