Objective To compare the differences between the cell swelling of cultured astrocytes (AST) from Wistar and Sprague-Dawley (SD) rats after incubation with glutamate. Methods Primary cultured AST derived from the cerebral cortex of one-day-old Wistar or SD rats were prepared. The cultured AST received 1 or 10 mmol/L glutamate treatment for 48 h on the tenth day after subculture. The viability of AST was determined by lactate dehydrogenase (LDH) kit to assess the cell injury, and the perimeter of AST was measured using Image Pro Plus software after glial fibrillary acidic protein immunofluorescence staining to evaluate the astrocyte swelling. Then, the expression of aquaporin 4 (AQP4) in cultured AST was detected by quantitative reverse transcription polymerase chain reaction. Results No significant difference was found in the LDH release after the glutamate treatment in cultured AST from these two strains (P>0.05). The perimeter of AST from normal Wistar rats was shorter than that from SD rats, but was longer after the treatment of glutamate (P<0.05). Meanwhile, AQP4 expression in the Wistar rats was significantly higher than that from SD rats after incubation with 1 mmol/L glutamate (P<0.05). Conclusions These results suggeste that cultured AST from Wistar rats are more susceptible to glutamate-induced swelling than that from SD rats, and there are differences between the effects of glutamate on AQP4 expression in astrocytes of Wistar and SD rats.