Neuroprotective Effect of Baicalin in a Rat Model of Permanent Focal Cerebral Ischemia


This investigation was performed to determine the neuroprotective effect of baicalin on permanent cerebral ischemia injury in rats and the potential mechanisms in this process. Adult male Sprague-Dawley rats underwent permanent middle cerebral artery occlusion (pMCAO). The rats were then received intraperitoneal injection with baicalin (10, 30 and 100 mg/kg) or vehicle. Morphological characteristic, neurological deficit scores, cerebral infarct volume and the enzymatic activity of myeloperoxidase (MPO) were measured 24 h after pMCAO. The mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were determined by RT-PCR. Neuronal apoptosis was determined by TUNEL staining and Western blot. Baicalin (30 and 100 mg/kg) reduced neurological deficit scores and cerebral infarct volume 24 h after pMCAO. Baicalin significantly decreased the enzymatic activity of MPO and the expression of iNOS mRNA and COX-2 mRNA in rat brain, it also significantly inhibited neuronal apoptosis and the expression of cleaved caspase-3 protein after pMCAO. Our results suggested that baicalin possesses potent anti-inflammatory and anti-apoptotic properties and attenuates cerebral ischemia injury. This protection might be associated with the downregulated expression of iNOS mRNA, COX-2 mRNA, and cleaved caspase-3 protein.

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The internal funding from the Department of Neurosurgery, The Affiliated Union Hospital of Fujian Medical University, supported this work.

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Correspondence to Wei-zhong Yang.

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Tu, X., Yang, W., Shi, S. et al. Neuroprotective Effect of Baicalin in a Rat Model of Permanent Focal Cerebral Ischemia. Neurochem Res 34, 1626–1634 (2009).

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  • Apoptosis
  • Baicalin
  • Cerebral ischemia
  • Inflammation
  • Neuroprotection
  • Stroke