Xpression of Aquaporin Water Channels in Mouse Spinal Ord

bstract—Aquaporins (AQPs) are membrane proteins inolved in water transport in many fluid-transporting tissues. quaporins AQP1, AQP4, and AQP9 have been identified in rain and hypothesized to participate in brain water hoeostasis. Here we use reverse transcriptase-polymerase hain reaction (RT-PCR), Western blotting and immunohistohemistry to describe the expression and immunolocalizaion of AQPs in adult mouse spinal cord. AQP4 was exressed in glial cells, predominantly in gray matter, and in strocytic end-feet surrounding capillaries in spinal cord hite matter. AQP9 expression extensively co-localized with lial fibrillary acidic protein-immunoreactive astrocytes, loated predominantly in the white matter. AQP5 was detected y RT-PCR but not by immunohistochemical analysis. Interstingly, AQP8 was detected primarily in ependymal cells ining the fluid-filled central canal. The aquaporin expression attern in spinal cord suggests involvement in water hoeostasis and diseases associated with abnormal water uxes such as spinal cord injury and syringomyelia. © 2004 ublished by Elsevier Ltd on behalf of IBRO.