Effect of L-arginine supplement on liver regeneration after partial hepatectomy in rats.
BACKGROUND
Nitric oxide (NO) has been reported to be a key mediator in hepatocyte proliferation during liver regeneration. NO is the oxidative metabolite of L-arginine, and is produced by a family of enzymes, collective termed nitric oxide synthase (NOS). Thus, administration of L-arginine might enhance liver regeneration after a hepatectomy. Another amino acid, L-glutamine, which plays an important role in catabolic states and is a crucial factor in various cellular and organ functions, is widely known to enhance liver regeneration experimentally. Thus, the present study was undertaken to evaluate the effects of an L-arginine supplement on liver regeneration, and to compared this with supplementation with L-glutamine and L-alanine (the latter as a negative control), using a rat partial hepatectomy model.


METHODS
Before and after a 70% hepatectomy, rats received one of three amino acid solutions (L-arginine, L-glutamine, or L-alanine). The effects on liver regeneration of the administered solutions were examined by assessment of restituted liver mass, staining for proliferating cell nuclear antigen (PCNA), and total RNA and DNA content 24 and 72 hours after the operation.


RESULTS
At 72 hours after the hepatectomy, the restituted liver mass, the PCNA labeling index and the DNA quantity were all significantly higher in the L-arginine and L-glutamine groups than in the control. There were no significant differences in those parameters between the L-arginine and L-glutamine groups, nor were any significant differences found between the L-alanine group and the control.


CONCLUSIONS
Oral supplements of L-arginine and L-glutamine enhanced liver regeneration after hepatectomy in rats, suggesting that an oral arginine supplement can clinically improve recovery after a major liver resection.
Division of Gastroenterological Surgery, Department of Surgery, Aichi Medical University School of Medicine, Nagakute, Aichi Pref 480-1195, Japan. tsuyok@masuko.or.jp
Tsuyoshi
T
Kurokawa
Jun
J
An
Koji
K
Tsunekawa
Yoshiharu
Y
Shimomura
Shunsuke
S
Kazama
Naohisa
N
Ishikawa
Toshiaki
T
Nonami
Satoru
S
Sugiyama
D000284:Administration, Oral; D000409:Alanine / Q000008:administration & dosage; D000818:Animals; D001120:Arginine / Q000008:administration & dosage*; D004247:DNA / Q000235:genetics; D005973:Glutamine / Q000008:administration & dosage; D006498:Hepatectomy; D007124:Immunoenzyme Techniques; D008107:Liver Diseases / Q000601:surgery*; D008115:Liver Regeneration / Q000187:drug effects*; D008297:Male; D016133:Polymerase Chain Reaction; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D012313:RNA / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar
D018809:Proliferating Cell Nuclear Antigen; D005973:Glutamine; D012313:RNA; D004247:DNA; D001120:Arginine; D000409:Alanine