[Protective effect of mild hypothermia on astrocytes with traumatic or ischemic injury].
OBJECTIVE
To investigate the protective effect of mild hypothermia on rat astrocytes with traumatic or ischemic injury.


METHODS
Rat astrocytes in primary culture were subjected to scratching or hypoxic injury and exposed to normothermia (37 degrees celsius;) or hypothermia (34 or 32 degrees celsius;) for 24 h. The morphology of the astrocytes was evaluated by live/dead staining, and the cell injury was measured by lactate dehydrogenase (LDH) release assay.


RESULTS
As the temperature reduced the LDH release rate from the cells in hypoxic group decreased significantly, to (11.48 - or + 1.53)% at 34 degrees celsius; and (3.79 - or + 0.45)% at 32 degrees celsius; as compared to that in normothermia [(33.02 - or + 3.58)%] in the absence of rat white blood cells (WBC) (P<0.001). LDH release rate of the hypoxic cells further decreased in the presence of rat WBC to (51.14 - or + 2.17 )% at 37 degrees celsius;, (19.53 - or + 4.37)% at 34 degrees celsius; and (16.68 - or + 1.47)% at 32 degrees celsius; (P<0.001). In the scratched cells, with or without WBC, LDH release rate showed no significant variation between the 3 temperatures (P>0.05).


CONCLUSIONS
Mild hypothermia offers obvious protective effects on rat astrocytes against ischemic damage but not against mechanical injury.
Cao
Qiong
Q
Research Center of Clinical Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. caoliy2000@126.com
Zhang
Lan-lan
LL
Hu
Zi-you
ZY
Wu
Bing-yi
BY
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000201:enzymology / Q000473:pathology*; D001930:Brain Injuries / Q000628:therapy*; D002545:Brain Ischemia / Q000628:therapy*; D015687:Cell Hypoxia; D002478:Cells, Cultured; D003080:Cold Temperature; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
D007770:L-Lactate Dehydrogenase