ABSTRACT
OBJECTIVE: To explore whether the protective mechanism of ginkgolide K on cerebral focal ischemia reperfusion injury in rats induced by middle cerebral artery occlusion (MCAO) was associated with the amelioration of mitochondrial calcium uniporter ( MCU) or not. METHODS: Sprague Dawley (SD) rats were divided into 5 big groups randomly: sham operation group, MCAO group, GK added into RR group, GK group and GK added into SM group. The MCAO rat model were established after cerebral artery ischemia for 2 h and reperfusion for 22 h. Zea Longa 5 score system was used to evaluate neurological deficit score; Determination of brain water content and cerebral infarction areas were determined using gravimetric method and by triphenyltetrazolium chloride(TTC) staining method, respectively. In addition, malondialdehyde (MDA) and superoxide dismutase (SOD), nitric oxide synthase (NOS), nitric oxide (NO) were detected by Elisa. Additionally, mitochondrial[Ca2+] i concentration was estimated with the fluorescence spectrophotomete. The morphological change of the injured brains were observed by HE staining. The expression of caspase-3/8/9 protein were detected by Western blot. RESULTS: Compared with GK group, GK + RR group relieved obviously the neurological deficit score and reduced the cerebral infarction areas, brain water content, mitochondrial[Ca2+]i concentration and MDA, caspase-3/8/9 protein expression while enhance SOD activity. However, the effect of SM on the GK protective activity in MCAO rat injury was the opposite in comparison to GK + RR group. CONCLUSION: The stimulative effect of RR and the inhibitory effect of SM on the GK protection in MCAO rat had proves that the protective mechanism of GK on MCAO rat injury is associate with its down-regulation of the transport capacity of MCU, leading the attenuation of mitochondrial[Ca2+]i influx.
ABSTRACT
Objective To explore the effect of hypoxia-ischemia(HI)on expression of second mitochondria-derived activator of caspase proteinc(Smac)in brain tissue of neonatal rats.Methods All neonatal rats were divided randomly into HI group,pseudo-operation group,and normal control group.The animal models of HIE were made.At 24,48,72,96 h after HI,Western blot was used to detect the expression of Smac protein in hippocampus.The relative activity of Caspase-3 in hippocampus tissue was determined by colorimetric assay.Results In HI group,at 24,48,72,96 h after HI,the expression levels of Smac protein in hippocampus significantly increased compared with that of pseudo-operation group and normal control group(Pa