[Expression of ET-3 in hippocampal CA1 of ovariectomied mice after cerebral ischemia/reperfusion].

Abstract

Objective: To detect the expression of endothelins-3 (ET-3) immunoactivity in hippocampal CA1 of ovariectomied (OVX) mice after ischemia/reperfusion (IR), and to further explore the relationship between estrogen and ET-3.

Methods: Fifty-four adult female mice were randomly divided into 3 groups. 1. IR group: the bilateral common carotid occlusion (BCCO) was carried out for 7 min on the 1st, 3rd, 5th and 14th day of reperfusion. 2. OVX/IR group: firstly the ovariectomy was performed, and after a week, BCCO was carried out for 7 min on the 1st, 3rd, 5th and 14th day of reperfusion (each time spot, n = 6). 3. sham-operated group (n = 6).

Results: Few ET-3 positive cells were diffusely distributed in the hippocampal CA1 region in the control group, whereas the expression of ET-3 increased in the experimental groups. The number of ET-3 positive cells significantly increased in the OVX/IR group compared with that of the IR group 1 d after the reperfusion (P < 0.01). It reached the maximum in both the OVX/IR and IR group on the 5th day of the reperfusion.

Conclusion: Estrogen is involved in the regulation of ET-3 in the early stage of the reperfusion, and probably plays a protective role in the survival of neurons.