Figure 5

Distribution of AQP1 and AQP4 in the control pons. ( a ) Myelin immunohistochemistry reveals the characteristic features of the basis pontis: transverse white matter pontocerebellar tracts (*) and descending white matter corticospinal and coticobulbar tracts (**) intermingled with pontine grey matter nuclei (x) (PLP, scale bar = 5 mm); ( b ) Pontine white matter astrocytes preferentially express aquaporin 1 (AQP1) (AQP1, scale bar = 5 mm); ( c ) Astrocytes in the pontine nuclei preferentially express aquaporin 4 (AQP4) (AQP4, scale bar = 5 mm); ( d ) AQP1 in the white matter is highly concentrated on the membrane of the astrocytic cell bodies (arrow heads) and in all astrocytic foot processes, including those abutting blood vessels (arrows) (AQP1, scale bar = 100 μm); ( e ) AQP1 immunoreactivity in the pontine nuclei is preferentially observed around blood vessels (arrows) and around some, but not all neurons (AQP1, scale bar = 50 μm); ( f ) AQP4 immunoreactivity in the white matter is mainly observed around blood vessels (arrows) (AQP4, scale bar = 100 μm); ( g ) AQP4 positive astrocytic processes in the pontine nuclei envelop the blood vessels (arrow) as well as all neuronal cell bodies (AQP4, scale bar = 50 μm).