BACKGROUND/AIMS: 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. METHODOLOGY: 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.

Adult↗

PubMedDate not supplied

Establishment and characterization of a cisplatin-resistant human neuroblastoma cell line.

BACKGROUND: To investigate the mechanisms of cisplatin (CDDP)-resistance in neuroblastoma(NB), we established a CDDP-resistant human NB cell line, BM1R2. MATERIALS AND METHODS: We characterized BM1R2 in terms of the susceptibilities to other anticancer agents, MDR1 and MRP expression, MYCN amplification, intracellular gultathione-S-transferase(GST-pi), metallothionein(MT) and gultathione(GSH) levels, and immunocytochemical and cytogenetic features. RESULTS: When compared to parent BM1 line, BM1R2 exhibited a 17.0-fold resistance to CDDP and cross-resistance to other agents. MRP expression was only observed in BM1R2, whereas MDR1 was expressed in both lines. Notably higher intracellular GST-pi and MT levels were observed in BM1R2 cells. MYCN amplifications were 50 and 6 copies in BM1 and BM1R2, respectively, and additional aberrations were observed in chromosome 1 and 2 in BM1R2. CONCLUSION: It was suggested that GST-pi and MT could exert crucial roles on CDDP-resistance in our system. BM1R2 is of great interest for investigating the mechanisms of CDDP-resistance in NB.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMedDate not supplied

Levels of interleukin (IL)-6, IL-8, and IL-1 receptor antagonist in the hepatic vein following liver surgery.

BACKGROUND/AIMS: The liver produces various cytokines, but local changes in the concentrations of these reaction products after liver surgery are unknown. We investigated the local changes of interleukin-6, interleukin-8 and interleukin-1 receptor antagonist after liver surgery. METHODOLOGY: We determined levels of interleukin-6, interleukin-8, and interleukin-1 receptor antagonist in the hepatic vein and radial artery after liver resection in 13 patients. These cytokine levels in the portal vein were also measured in 6 patients. RESULTS: Interleukin-6, interleukin-8, and interleukin-1 receptor antagonist levels were significantly increased during liver surgery (P < 0.05). The level of interleukin-6 was significantly lower in the hepatic vein than in the radial artery as well as in the portal vein at the end of the operation (P < 0.05, < 0.03). The level of interleukin-8 and interleukin-1 receptor antagonist was significantly higher in the hepatic vein than in the artery (P < 0.05). CONCLUSIONS: Interleukin-6 may be taken up by the liver after liver surgery, and the difference between hepatic venous and peripheral arterial interleukin-6 levels may be an indicator of liver regeneration after liver resection. Interleukin-8 and interleukin-1 receptor antagonist appear to be produced in the remaining liver.

Aged↗