Effect of normothermic liver ischemic preconditioning on the expression of apoptosis-regulating genes C-jun and Bcl-XL in rats.
OBJECTIVE
To explore the expression of apoptosis-regulating genes C-jun and Bcl-XL after normothermic liver ischemic preconditioning and its protective effect on hepatocytes in the rat.


METHODS
Wistar rats are randomly divided into sham operation group (S group, n = 10), ischemic reperfusion group (IR group, n = 10) and ischemic preconditioning group (IP group, n = 10). After dissection of the hepatoduodenal ligament in S group, and after 30-min reperfusion in IR group and in IP group, the samples of liver tissue were taken for studying the hepatocellular apoptosis, the expressions of C-jun mRNA, Bcl-XL mRNA and their proteins, and morphologic changes at 0, 3, 6, 20 h. Meanwhile the venous blood samples were drawn at 3, 6 and 20 h for testing ALT, AST and LDH.


RESULTS
The levels of ALT, AST and LDH in IR group and IP group were significantly higher than those in S group. Hepatocellular apoptosis was significantly increased in both IR group and IP group, especially in IR group. Expressions of C-jun mRNA and protein were significantly increased in IR group compared with those in both IP group and S group, but no significant difference between IP group and S group (P>0.05). Expressions of Bcl-XL mRNA and protein in IR group and S group were not significant (P>0.05), but were significantly increased in IP group compared with those in both S group and IR group. Patch necrosis of hepatocytes because of severe injury could be seen in IR group microscopically, and the ultrastructural changes were irreversible. Meanwhile in IP group, no hepatocellular necrosis occurred, and the ultrastructural changes were reversible because of mild injury.


CONCLUSIONS
(1) IP can protect the rat liver from normothermic IR injury by modulation of the expression of apoptosis-regulating genes C-jun and Bcl-XL; (2) IR injury may activate the apoptosis of hepatocytes by increasing the expression of apoptosis-inducing gene C-jun; (3) IP may prohibit the apoptosis of hepatocytes by increasing the expression of apoptosis-inhibitory gene Bcl-XL.
Hu
Guo-Huang
GH
Department of General Surgery, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China.
Lu
Xin-Sheng
XS
D000818:Animals; D017209:Apoptosis; D015870:Gene Expression; D016758:Genes, jun / Q000502:physiology*; D022781:Hepatocytes / Q000166:cytology* / Q000502:physiology; D019194:Ischemic Preconditioning / Q000379:methods*; D008297:Male; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D051381:Rats; D017208:Rats, Wistar; D013696:Temperature; D051020:bcl-X Protein
C494813:Bcl2l1 protein, rat; D019253:Proto-Oncogene Proteins c-bcl-2; D051020:bcl-X Protein