Enhanced expression of cytosolic fatty acid binding protein and fatty acid uptake during liver regeneration in rats.
OBJECTIVE
Cytoplasmic liver fatty acid binding protein (L-FABP) has been suggested to be associated with cellular mitotic activity but the changes in L-FABP mRNA and protein levels during liver regeneration following partial hepatectomy (PHx) are not clear.


METHODS
In the present study, we determined the time course of L-FABP mRNA expression and L-FABP levels following 70% PHx using Northern and Western blot, respectively. To elucidate one of the roles for L-FABP in PHx, [3H]-palmitic acid clearance in hepatocytes isolated from 24 h post-PHx and control animals was assessed.


RESULTS
L-FABP mRNA increased at 30 min, peaked at approximately 1 h (163 +/- 17%; mean +/- SE, n = 5), and returned to control levels 6 h post-PHx. L-FABP level also increased at 1 h but peaked at 24-h (219 +/- 41%; mean +/- SE, n = 5). Hepatocyte [3H]-palmitic acid clearance increased by 29% at 24-h post-PHx, suggesting an increased intracellular transport (or binding) function by L-FABP. Pre-treatment with dexamethasone statistically reduced L-FABP levels (29%) and suppressed the regenerative process (mitotic activity).


CONCLUSIONS
L-FABP mRNA increased sharply in response to PHx but the increase was short lived, while L-FABP level increased at a later stage. Both L-FABP content and fatty acid uptake increased significantly during liver regeneration induced by PHx in rats. It is likely that L-FABP is one of the factors responsible for hepatic regeneration.
Wang
GuQi
G
Faculty of Pharmacy, University of Manitoba, Winnipeg, Manitoba, Canada.
Chen
Qing Ming
QM
Minuk
Gerald Y
GY
Gong
Yuewen
Y
Burczynski
Frank J
FJ
D000818:Animals; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics* / Q000502:physiology; D003600:Cytosol / Q000737:chemistry; D003907:Dexamethasone / Q000008:administration & dosage / Q000494:pharmacology; D050556:Fatty Acid-Binding Proteins; D005786:Gene Expression Regulation / Q000502:physiology*; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D008115:Liver Regeneration; D008297:Male; D023421:Models, Animal; D019308:Palmitic Acid / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014316:Tritium
D002352:Carrier Proteins; C493321:Fabp1 protein, rat; D050556:Fatty Acid-Binding Proteins; D012333:RNA, Messenger; D014316:Tritium; D019308:Palmitic Acid; D003907:Dexamethasone