Expression of aquaporin-4 protein in the brain of preeclampsia model rats

Objective To study the expression of aquaporin-4(AQP4) protein in preeclampsia(PE) model rats.Methods Adult SD rats were divided into PE model group(n=7) induced by endotoxin,normal pregnancy group(n=6) and non-pregnancy group(n=12) treated with an equal volume of saline.AQP4 protein expression in the brain of the rats was detected with immunohistochemical staining and Western blotting.Results The blood pressure in PE model rats(135 ± 9 mmHg) was significantly higher than that in normal pregnancy rats(116±8 mmHg) and non-pregnancy rats(112±6 mmHg)(P0.02).The rats in PE model group showed obvious proteinuria compared with the other two groups(3.8±0.5 vs 2.6±0.6 and 2.3±0.4,P 0.05).Immunohistochemistry showed that AQP4 protein was localized primarily around the brain parenchymal blood vessels.Western analysis revealed a significantly elevated AQP4 protein expression in PE model group(39.6±4.9) compared with that in normal pregnancy group(26.5 ± 4.3) and non-pregnancy group(9.7 ± 2.1)(P0.01).Conclusion The up-regulation of AQP4 protein around the intraparenchymal blood vessels of the brain may play a role in the development of eclampsia.