Regenerative capacity of normal and irradiated liver following partial hepatectomy in rats.
OBJECTIVE
To investigate the regenerative capacity and proliferation related to cell cycle modulators in irradiated livers after partial hepatectomy (PH) in rats.


METHODS
Two experimental groups were given a single dose of either 4-Gy or 8-Gy photon radiation to the whole liver following PH. The control group underwent only PH, without irradiation. The liver specimens were analysed for apoptosis, proliferation and cell cycle related genes between 0.5 and 12 days.


RESULTS
Mean change in weight of the remnant liver in the 8-Gy group was significantly lower than in the control and 4-Gy groups. The apex of proliferating cell nuclear antigen labelling and bromodeoxyuridine incorporation index in two irradiated groups were also apparently lower than that in control group. After PH, transforming growth factor beta-1 (TGFbeta1), and the type II receptor of TGFbeta (TGFbetaR-II), anti-tumour protein 53(p53) and anti-tumour protein21(p21) protein expression in the irradiated livers was higher than in unirradiated ones. Significant apoptosis was noted in 8-Gy group. However, the maximal value of hepatocyte growth factor (HGF) mRNA and protein expression in the irradiated group was suppressed and restoration of liver function was delayed.


CONCLUSIONS
Whole liver lower dose irradiation can attenuate regenerative capacity following partial hepatectomy in rats.
Du
Shi-Suo
SS
Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032,China.
Zeng
Zhao-Chong
ZC
Tang
Zhao-You
ZY
Zhang
Zheng-Yu
ZY
Shi
Liu-Sheng
LS
Wu
Zheng
Z
Qiang
Ming
M
Liu
Zhong-Shan
ZS
D000818:Animals; D017209:Apoptosis / Q000502:physiology / Q000528:radiation effects; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D006498:Hepatectomy; D017228:Hepatocyte Growth Factor / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D008099:Liver / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects* / Q000601:surgery*; D008115:Liver Regeneration / Q000502:physiology / Q000528:radiation effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011829:Radiation Dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
D050759:Cyclin-Dependent Kinase Inhibitor p21; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D016159:Tumor Suppressor Protein p53; D017228:Hepatocyte Growth Factor