[Ultrastructural features of cultured rat cortical astrocytes with stretch-induced injury].
OBJECTIVE
To investigate the changes of ultrastructural features of cultured rat cortical astrocytes after stretch-induced injury.


METHODS
Rat cortical astrocytes isolated from 1- to 2-day-old rats were cultured till confluency, and then plated in tissue culture wells with flexible silastic bottom after purification. A computer-controlled device was used to produce stretch-induced injury in the astrocytes with the imposed pressure of 50, 150, and 250 kPa respectively, followed by observation of the ultrastructural changes in the astrocytes with light and electron microscopy.


RESULTS
Obvious ultrastructural destruction of the astrocytes occurred when the imposed stretch pressure was 50 kPa, and scanning electron microscopy demonstrated increased intercellular space and laceration of the cell body and its processes. Transmission electron microscopy revealed mitochondria swelling 1 h after stretch-induced injury and 6 h after the injury, vacuolar degeneration of the mitochondria occurred. Increased stretch pressure caused further decrease in the amount of glial filaments and densification of astrocytes.


CONCLUSIONS
Stress, even at a relatively small scale, can cause disruption of intercellular juncture and ultrastructural change of the cultured astrocyte, which may be related with extensive brain edema after traumatic brain injury.
Wang
Ke-Wan
KW
Department of Neurosurgery, Nanfang Hospital, First Military Medical University, Guangzhou 510515, China.
Qi
Song-Tao
ST
Yang
Zhi-Huan
ZH
Wang
Zheng-Guo
ZG
Zhu
Pei-Fang
PF
Yang
Kai-Jun
KJ
Liu
Cheng-Yong
CY
Huang
Li-Jin
LJ
D000818:Animals; D001253:Astrocytes / Q000648:ultrastructure*; D002478:Cells, Cultured; D009457:Neuroglia / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D013314:Stress, Mechanical