Rat Model Of Permanent Ischemia Research Articles

Effect of Tongli Shuji acupuncture on the expression of Jagged2 and Notch2 in a rat model of permanent ischemia of the right middle cerebral artery

To investigate the effect of Tongli Shuji acupuncture on the behavioristics, the percentage of cerebral infarct volume, and the expression of Jagged2 and Notch2 proteins in the hippocampus of the ischemic hemisphere in rats with permanent ischemia of the right middle cerebral artery, as well as the mechanism of Tongli Shuji acupuncture in improving ischemic cerebrovascular disease. Sprague-Dawley rats were randomly divided into sham-operation group, model control group, medication group, routine acupuncture group, and Tongli Shuji group, with 10 rats in each group. The suture method was used to establish a model of permanent ischemia of the right middle cerebral artery. The rats in the medication group were given Citicoline (0.4 mg/kg) by gavage, those in the routine acupuncture group were given acupuncture at"Baihui"(GV20) and"Dazhui" (GV14) 15 minutes per day, and those in the Tongli Shuji group were given acupuncture at "Zhengying "(GB17), "Tianjing"(SJ10), and"Huantiao"(GB30) at the left side. The neurological deficit score was determined on days 1, 7, 14, 21 and 28 after surgery, the percentage of cerebral infarct volume was measured after treatment, and Western blot was used to measure the protein expression of Jagged2 and Notch2 in the right hippocampal tissue. Compared with the sham-operation group, the model control group had significant increases in the neurological deficit score on day 1 after surgery (P<0.001). Compared with the model control, medication and routine acupuncture groups, the Tongli Shuji group had significant reductions in the neurological deficit score on day 21 after surgery (P<0.01). Compared with the sham-operation group, the model control group had a significant increase in the percentage of cerebral infarct volume(P<0.05)．The Tongli Shuji group had a significant reduction in the percentage of cerebral infarct volume compared with the medication groups (P<0.05). Compared with the model control group, the routine acupuncture group had a significant increase in the expression of hippocapmal Jagged2(P<0.01)．Compared with the model control, medication and routine acupuncture groups, the Tongli Shuji group had significant increases in the expression of hippocampal Jagged2 and Notch2 (P<0.01). Acupuncture can improve the behavioral manifestations of neurological deficit in rats with permanent ischemia of the right middle cerebral artery. Tongli Shuji acupuncture can significantly up-regulate the protein expression of Jagged2 and Notch2 in the hippocampal tissue of the ischemic region, possibly by activating the Notch signaling pathway to exert a neuroprotective effect.

Matrix Metalloproteinase-13 is Activated and is found in the Nucleus of Neural Cells after Cerebral Ischemia

Matrix metalloproteinases (MMPs) have been implicated in the pathophysiology of ischemic stroke. In this study, we investigated the time course of gelatinolytic activation in a rat model of permanent ischemia. We observed an activation of MMPs as early as 30 mins after the ischemic insult, mainly in the nuclei of brain cells. Besides, we explored MMP-13 expression in brain samples of the animal model and stroke deceased patients. We observed an upregulation of active MMP-13 in rat brains (P<0.05) after 90 mins of cerebral ischemia. Human infarct/periinfarct samples also showed higher levels of active MMP-13 (P<0.05) compared with contralateral ones. Interestingly, we found that MMP-13 colocalized with 46-diamidino-2-phenyl indole signal by immunohistochemistry in both humans and rats, suggesting an intranuclear localization for MMP-13. Immunohistochemistry also revealed that MMP-13 was mainly produced by neurons, in both species, but also by oligodendrocytes in rats, and by astrocytes in humans. Finally we subjected a rat primary neuronal culture to oxygen and glucose deprivation (OGD) and we reproduced the nuclear translocation of MMP-13 in vitro. Nuclear extracts from cells confirmed upregulation of active MMP-13 after OGD (P<0.05). These results suggest that MMP-13 activation and its nuclear translocation is an early consequence of an ischemic stimulus.