Effect of lactation on hippocampal neuronal density after global ischemia

Background: After heart diseases, stroke is the most common cause of mortality worldwide and the leading cause of longtermacquired disability. Ischemic stroke is a devastating event caused by insufficient cerebral circulation of blood whichtriggers a cascade of pathophysiologic events resulting in tissue damge and brain dysfunction. One of the cerebral areashighly vulnerable to reduced blood flow is the CA1 region of hippocampus. Pregnancy and lactation are a time of enhancedneural plasitcity associated with increased neurogenesis and neuronal survival. This effect is mediated by dramaticfluctuations of steroid hormones and peptide hormones. Therefore, it seems likely that pregnancy and lactation can conferneuroprotection against cerebral ischemic injury. The current study was designed to assess the effects of pregnancy andlactation on neural density in rats undergoing global ischemia.Material and methods: Thus, we examined neural density after global cerebral ischemia (occlusion of the common carotidarteries was induced for 20 minutes) in Thirty-two female Wistar rats in the four groups (n=8): Pregnancy-lactation group(P-L), Virgin-ischemic group (V-Isc), Pregnancy-ischemic group (P-Isc) and Pregnancy-lactation-ischemic group (P-LIsc).Results: According to analysis, hippocampal neural density in Pregnancy-lactation-ischemic group was significantly morethan Pregnancy-ischemic and Virgin-ischemic groups (P<0.05).Conclusion: the present experiment provide new evidence that reproduction experiences Protect brains toward ischemicattack by related hormones that leads to increase in neurogenesis.

Keywords:

Stroke , Ischmic stroke , Cerebral ischemia , Lactation , Hippocampal neural density