Premium
Type II sodium channels in spinal cord astrocytes in situ: Immunocytochemical observations
Author(s) -
Black Joel A.,
Westenbroek Ruth,
Ransom Bruce R.,
Catterall William A.,
Waxman Stephen G.
Publication year - 1994
Publication title -
glia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.954
H-Index - 164
eISSN - 1098-1136
pISSN - 0894-1491
DOI - 10.1002/glia.440120307
Subject(s) - spinal cord , sodium channel , biology , white matter , gene isoform , central nervous system , astrocyte , anatomy , neuroglia , optic nerve , immunocytochemistry , neuroscience , pathology , sodium , microbiology and biotechnology , chemistry , endocrinology , biochemistry , medicine , organic chemistry , radiology , gene , magnetic resonance imaging
The expression of sodium channel α‐subunit isoforms in astrocytes in adult rat spinal cord and optic nerve was examined utilizing immunocytochemical methods with antibodies generated against conserved and subtype‐specific sequences of the sodium channel. In adult rat spinal cord, astrocytes within the dorsal and ventral funiculi were immunolabelled with antibody SP20, which recognizes a conserved sequence within sodium channel types I, II, and III. In addition, astrocytes within these spinal cord white matter tracts were immunostained with antibody SP11‐II, which recognizes sodium channel type II. Antibodies SP11‐I and SP32‐III, which are directed against subtype‐specific sequences in sodium channel types I and III, respectively, did not label astrocytes in the dorsal and ventral funiculi of the spinal cord. In optic nerves, astrocytes were immunostained with antibody SP20. However, no detectable labelling of cells within the optic nerve was observed with antibodies SP11‐I, SP11‐II, and SP32‐III. These observations demonstrate that sodium channel II is expressed by astrocytes in spinal cord white matter. Moreover, these data suggest that regional factors regulate the level of sodium channel isoform expression in astrocytes.