The subgroup change of nitric oxide synthase in earlier period with cerebral ischemia/reperfusion in rats

Objective: To observe the expression of endothelial nitric oxide synthase (eNOS)and nervous nitric oxide synthase (nNOS) in rats during cerebral ischemia/reperfusion (CI/R) and study if change will be happen in subgroup between eNOS and nNOS during earlier period of CI/R.

Methods: A total of 60 Wistar rats weighting 200-280 g, supplied by Animal Center of China Medical University, were divided into 6 groups (n=10) (sham operation group; ischemia 1 h, 2 h group; reperfusion 0.5 h, 1 h, 2 h group). Female and male was half-and-half. Cerebral ischemia/reperfusion injury was induced by a 2-hour suture occlusion of the unilateral middle cerebral artery, immediately after suture withdrawal to allow reperfusion, eNOS and nNOS expressions were examined by the method of immunohistochemistry.

Results: eNOS expressions increased in 1-hour during ischemia, keeping up with decreasing until reperfusion 2-hour. While nNOS expressions increased in 2-hour between ischemia and reperfusion.

Conclusions: Changes of expression between eNOS and nNOS in rats during cerebral ischemia/reperfusion are different. This may be related with ischemia and reperfusion injury.