Abstract: Abstract: Objective To investigate changes of the elastic modulus of astrocytes induced by injury. Methods The astrocytes were isolated and extracted from the 2-day old SD rats, and identified by immunofluorescence staining with glial fiber acidic protein (GFAP) antibody. Cells were divided into control group and injured group. The injured group was astrocytes 6 h after being injured by the cell damage instrument. The control group was astrocytes without any injury. The elastic modulus in liquid phase was tested by atomic force microscope in two groups. Results were compared and analyzed between two groups. Results The purification rate of rat astrocytes was more than 95% . Six hours after the injury, the astrocytes were in disorder, and some of cell bodies were swelling. The mechanical topographic maps and force indentation curves were obtained. The elastic modulus of astrocytes was significantly increased in injured group compared with that of control group［(1 689±693) Pa vs. (724±283) Pa, P＜0.01]. Conclusion The injury stimulus increases the elastic modulus of astrocytes, which provides theoretical basis for understanding intracranial physical microenvironment after traumatic brain injury in animal experiments.

Key words: microscopy, atomic force, atomic force microscope, astrocyte, cell injury, elastic modulus