[The best site of transplantation of neural stem cells into brain in treatment of hypoxic-ischemic damage: experiment with newborn rats]

Abstract

Objective: To investigate the best site of transplantation of neural stem cells (NSCs) into the brain to treat hypoxic-ischemic damage (HIBD).

Methods: Forty-eight 7-day-old Spraque-Dawley rats underwent ligation of the left common carotid artery and exposure to 8% oxygen at 37 degrees C for 2 hours to establish HIBD models and then were randomly divided into 4 equal groups 3 days later: HIBD control group, HIBD + cortex transplantation group (CT group) undergoing NSC transplantation into the sensorimotor cortex, HIBD + hippocampus transplantation group (HT group) undergoing NSC transplantation into the hippocampus, and HIBD + ventricle transplantation group (VT group), undergoing NSC transplantation into the lateral ventricle. Since the rats were 40-day-old, they underwent radial maze water-seeking test and 4 sensorimotor tests. Then the brains of the rats were taken out to undergo histological examination by Nissl staining and immunohistochemistry to observer the 5-bromodeoxyuridine (BrdU) expression.

Results: The times the rats took to find the water in all 3 arms of the maze were arranged form short to long in the order HT group < VT group < CT group < HIBD group with significant differences between the HT, VT, and CT groups and HIBD group (All P < 0.05) and between the groups HT and VT and the group CT (both P < 0.05). The results of the 4 sensorimotor tests were arranged from the best to the worst in the order CT group > VT group > HT group > HIBD group with significant differences between the groups CT and VT and the group HIBD (both P < 0.05). Nissl staining showed that the number of normal neurons in the cortex area from more to less were arranged in the order CT group > VT group > HT group > HIBD group; and the number of normal neurons in the CAI area from more to less were arranged in the order HT group > VT group > CT group > HIBD group.

Conclusion: Transplantation of NSC attenuates the brain damage and the cognitive and sensorimotor dysfunction after HIBD. Transplantation into the lateral ventricle is the most effective.