Animal models of cerebral ischemia for evaluation of drugs

Stroke is a major cause of death and disability worldwide. The resulting burden on the society continues to grow, with increase in the incidence of stroke. Brain attack is a term introduced to describe the acute presentation of stroke, which emphasizes the need for urgent action to remedy the situation. Though a large number of therapeutic agents like thrombolytics, NMDA receptor antagonists, calcium channel blockers and antioxidants, have been used or being evaluated, there remains a large gap between the benefits by these agents and properties an ideal drug for stroke should offer. In recent years much attention is being paid towards the exploration of herbal preparation, antioxidant agents and combination therapies including COX-2 inhibitors in experimental model of stroke. For better evaluation of the drugs and enhancement of their predictability from animal experimentation to clinical settings, it has been realized that the selection of animal models, the parameters to be evaluated should be critically assessed. Focal and global cerebral ischemia represents diseases that are common in the human population. Understanding the mechanisms of injury and neuroprotection in these diseases is important to learn new target sites to treat ischemia. There are many animal models available to investigate injury mechanisms and neuroprotective strategies. In this article we attempted to summarize commonly explored animal models of focal and global cerebral ischemia and evaluate their advantages and limitations.