Effect of thyroid hormones on expressions of CytC and AIF after cerebral ischemia-reperfusion injury in rats / 实用医学杂志

ABSTRACT

Objective To investigate the effect of thyroid hormone(T3)on the expressions of cytochrome c (CytC) and apoptosis?inducing factor(AIF) after cerebral ischemia reperfusion injury in rats and its mechanism. Methods SD male rats were randomly divided into four groups sham operation group(sham1),sham operation group + T3(sham2) ,ischemia?reperfusion group (IR) ,and thyroid hormone treatment group(T3). A rat model of cerebral ischemia?reperfusion injury was established by right middle cerebral artery occlusion for 2 h,followed by reperfusion for 24 h. Thyroid hormones (10μg/100 g) or normal saline were given at 1 h after onset of ischemia and 6 h after reperfusionby intraperitoneal injection. Neurological deficit scores were evaluated 24 h after reperfusion. Cerebral infarction volume was evaluated by TTC staining. Histological changes was observed by HE staining. Expressions and mRNA levels of CytC and AIF in ischemic brain tissue were evaluated by immunohistochemistry and real?time fluorescent quantitative RT?PCR. Results Ascompared with those in sham operation groups ,the expressions and mRNA levels of CytC and AIFincreased significantlyin IR groups. As compared with those in IR groups ,the indexes were remarkably decreasedin T3 groups (P < 0.01). Nerve function was markedly improved andinfarction area narrowed.Conclusions Thyroid hormone plays a certain role in protection of cerebral ischemia?reperfusion injury in rats,whose mechanism may be associated with inhibition of the expression of apoptosis factors?CytC and AIF.