Recovery of cerebral ATP generation following cerebral ischaemia is impaired when the ischaemia occurs in the setting of hyperglycaemic patients, particularly above blood glucose level of 225 mg/dl22.
In general, the brain has been considered as an insulin independent organ; moreover, insulin receptors have been identified in rat brain. Insulin also regulates ornithine decarboxylase activity, which regulates the synthesis of polyamines in the brain. Recently, insulin receptors have been found on the endothelium of cerebral microvessels, on platelets, and throughout the brain. Therefore, insulin may exercise beneficial effect on ischaemic stroke by enhancing the survival of neurons in the ischaemic zones23.