Mitochondrial ultrastructure & release of proteins during liver regeneration.
OBJECTIVE
It has been reported that some proteins are released from mitochondria during liver regeneration after partial hepatectomy (PH), but the relationship between proteins release and mitochondrial permeability transition (MPT) remains unclear. We undertook this study to demonstrate the changes of mitochondrial ultrastructure and proteins release during liver regeneration and to determine the relationship between proteins release and MPT in liver regeneration in rats.


METHODS
After PH and administration of cyclosporin-A (CsA, a specific inhibitor of MPT), ultrastructural morphology of mitochondria in the remnant liver were determined by electron microscopy. Catalytic activity of mitochondrial and cytosolic proteins including aspartate aminotransferase (AST) and glutamic acid dehydrogenase (GDH) was measured.


RESULTS
The liver mitochondria at 24 and 72 h were quite variable in morphology and ultrastructure. The enzyme activities of AST and GDH in cytosol released from mitochondrial matrix changed significantly at 24 and 72 h. CsA can inhibit the permeability of mitochondria partly at the same time.


CONCLUSIONS
The changes of mitochondria in ultrastructure reflected the feature of MPT, and the changes of enzymes activities released from mitochondrial matrix were consistent with those of mitochondrial ultrastructure. CsA can inhibit these changes to some extent. There was a close relationship of MPT with mitochondrial ultrastructure and proteins release during liver regeneration.
Zhou
Yun-Heng
YH
Department of Biochemistry & Molecular Biology, The Second Military of Medical University, Shanghai, PR China.
Shi
Duo
D
Yuan
Bin
B
Sun
Qing-Ju
QJ
Jiao
Bing-Hua
BH
Sun
Jing-Jian
JJ
Miao
Ming-Yong
MY
D000704:Analysis of Variance; D000818:Animals; D024442:Aspartate Aminotransferase, Mitochondrial / Q000378:metabolism; D016572:Cyclosporine; D006498:Hepatectomy; D022781:Hepatocytes / Q000378:metabolism* / Q000648:ultrastructure*; D008115:Liver Regeneration / Q000502:physiology*; D008297:Male; D008854:Microscopy, Electron; D008928:Mitochondria / Q000648:ultrastructure*; D010539:Permeability; D051381:Rats
D016572:Cyclosporine; D024442:Aspartate Aminotransferase, Mitochondrial