Down-regulation of immediate early gene egr-1 expression in rat C6 glioma cells by short-term exposure to high salt culture medium
- Resource Type
- Authors
- Kyoji, Morita; Hideki, Arimochi; Shigeru, Yoshida
- Source
- Cell biology international. 29(4)
- Subject
- Saline Solution, Hypertonic
Veratridine
Osmolar Concentration
Sodium
Down-Regulation
Glioma
Culture Media
Immediate-Early Proteins
Rats
DNA-Binding Proteins
Gene Expression Regulation
Cell Line, Tumor
Animals
Calcium
Monensin
Genes, Immediate-Early
Early Growth Response Protein 1
Transcription Factors
- Language
- ISSN
- 1065-6995
Influence of high salt culture conditions on the expression of immediate early gene egr-1 in rat C6 glioma cells was investigated by measuring both Egr-1 mRNA and protein levels in the cells exposed to the medium containing high concentrations of NaCl. The exposure to high salt medium reduced Egr-1 mRNA and protein levels, while Egr-1 mRNA levels were not altered by the medium containing either sucrose or glycerol. Veratridine and monensin also reduced Egr-1 mRNA levels, similar in extent to that induced by high salt medium. Imaging analysis indicated that the exposure to high salt medium induced the elevation of Na+ levels within the cells. These results indicate that neither hyperosmotic pressure nor ionic strength of high salt medium contribute to the reduction of Egr-1 expression, and suggest that the elevation of intracellular Na+ concentration is closely associated with the down-regulation of egr-1 gene expression.