Objective To determine whether aquaporin-4(AQP4)regulates acute lesions,delayed lesions,and the associated microglial activation after cryoinjury to the brain.Methods Brain cryoinjury was applied to AQP4 knockout(KO)and wild-type mice.At 24 h and on days 7 and 14 after cryoinjury,lesion volume,neuronal loss,and densities of microglia and astrocytes were determined,and their changes were compared between AQP4 KO and wild-type mice.Results Lesion volume and neuronal loss in AQP4 KO mice were milder at 24 h following cryoinjury,but worsened on days 7 and 14,compared to those in wild-type mice.Besides,microglial density increased more,and astrocyte proliferation and glial scar formation were attenuated on days 7 and 14 in AQP4 KO mice.Conclusion AQP4 deficiency ameliorates acute lesions,but worsens delayed lesions,perhaps due to the microgliosis in the late phase.
Wen-Zhen Shi Chun-Zhen Zhao Bing Zhao Xiao-Liang Zheng San-Hua Fang Yun-Bi Lu Wei-Ping Zhang Zhong Chen Er-Qing Wei
