Aquaporin in optic neuropathies

Abstract

The aquaporins (AQPs) are plasma membrane water-transporting proteins. Many AQPs have been identified as playing essential roles in the nervous system and in ocular functions. The AQPs are potential drug targets for several neurological conditions. Additionally, recent evidence has demonstrated that some AQPs are involved in the pathophysiology of optic neuropathies. Notably, AQP4, a pure water channel expressed at astrocytes in the optic nerve, is the first target of neuromyelitis optica (NMO) in optic neuritis. AQP9 facilitates the transport of lactate for neural energy metabolism and may be considered an essential factor for retinal ganglion cell survival. This review summarizes the expression and known functions of the ocular AQPs related to optic neuropathies.