Decreased hepatic nitric oxide synthesis during liver surgery.
OBJECTIVE
Liver cells can produce nitric oxide from L-arginine through the action of nitric oxide synthase, but local changes in the concentrations of nitric oxide-related metabolites during liver surgery are not well characterized. We investigated such changes during and after liver surgery.


METHODS
We determined nitrite plus nitrate, L-arginine and L-citrulline concentrations in radial arterial and hepatic venous blood during and after liver surgery in 17 patients. Portal venous blood concentrations were also measured at the end of surgery in 7 patients.


RESULTS
Both arterial and hepatic venous nitrite plus nitrate concentrations were significantly decreased during surgery and remained low compared to pre-operative values until post-operative day 2. Arterial and hepatic venous nitrite plus nitrate concentrations were not significantly different. L-arginine concentrations in both arterial and hepatic venous blood were significantly decreased during surgery, but returned to pre-operative levels on post-operative day 1. L-arginine concentrations in hepatic venous blood were significantly lower than in arterial blood. L-citrulline concentrations in both arterial and hepatic venous blood were significantly decreased during surgery compared to pre-operative values, and tend to be decreased until post-operative day 2. L-citrulline concentrations were significantly higher in hepatic venous blood than in arterial blood.


CONCLUSIONS
Hepatic nitric oxide production was decreased peri-operatively during liver surgery. The decreases in L-arginine concentrations and in nitric oxide synthase activity may account for the decrease in nitric oxide production.
Ueda
T
T
Department of Anesthesiology-Resuscitology, Yamaguchi University School of Medicine, Ube, Japan.
Sakabe
T
T
Oka
M
M
Maeda
Y
Y
Nishida
M
M
Murakami
F
F
Maekawa
T
T
D000328:Adult; D000368:Aged; D001120:Arginine / Q000097:blood; D006528:Carcinoma, Hepatocellular / Q000097:blood / Q000601:surgery*; D002956:Citrulline / Q000097:blood; D005260:Female; D006498:Hepatectomy; D006801:Humans; D008111:Liver Function Tests; D008113:Liver Neoplasms / Q000097:blood / Q000556:secondary / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000097:blood*; D009573:Nitrites / Q000097:blood; D012016:Reference Values
D009566:Nitrates; D009573:Nitrites; D002956:Citrulline; D009569:Nitric Oxide; D001120:Arginine