The. Catalpol Impaired Neuroprotective Effects Against Cerebral Ischemia

Mongolian gerbils have been widely used in the experimental study on ischemia-reperfusion injury due mainly to their deficiency in cerebral blood flow between the posterior arteries and the common carotid arteries.In this study, the model of gerbils' ischemia-reperfusion injury was used for approaching the biological effect of catapol. The animal was Consecutively administered catalpol (i.p. mg/kg) for 4days, killed and did assaies. The result showed that Catalpol increased markedly the expression of microtubule associated protein-2 (MAP-2), the number of live neurons in hippocampal CA1 and learning ability of runing Y-Maze. For gerbils whose cognitive ability is innate weak, catalpol can't ameliorate the learning and memory function. Summarily, these suggested that catalpol was a predominant neuroprotective candidate.by using electron microscope, flow cytometric analysis and TTC dye, found that the possible neuroprotective mechanism of catalpol was that catalpol inhibited cell apoptosis. Moreover, immunohistochemistry showed that catalpol could effectively promote the up-regulation of Bcl-2 protein and suppress ischemia-induced increase in Bax protein, by which apoptotic cell was inhibited to death and neurons were rescued.The activities of GSH-PX, SOD, CAT, NOS together with the contents of MDA in hippocampus were determined. The results showed that catalpol not only could incease antioxidation ability, but also could inhibit the activities of NOS. These effects reduced the contents of Reactive oxygen species (ROS), and decreased the oxidation press of the neurons. Catalpol exerted its effect of neuroprotection by inhibiting cell oxidation.