Open AccessEffect of nitric oxide release from NOR-3 on urea synthesis, viability and oxygen consumption of rat hepatocyte cultures
Author(s) -
R. Chimenti,
Giuseppe Martino,
S. Mazzulla,
Settimio Sesti
Publication year - 2007
Publication title -
physiological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.647
H-Index - 70
eISSN - 1802-9973
pISSN - 0862-8408
DOI - 10.33549/physiolres.931039
Subject(s) - nitric oxide , hepatocyte , viability assay , urea , chemistry , oxygen , trypan blue , biochemistry , cell , in vitro , organic chemistry
As nitric oxide is considered a mediator of liver oxidative metabolism during sepsis, we studied the effects of exogenous nitric oxide, produced by NO-donor, (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR-3), on cell viability, urea biosynthesis and oxygen consumption in rat hepatocyte cultures. Nitric oxide release from NOR-3 was studied using 4,5-diaminofluorescein diacetate. Urea levels were measured by the spectrophotometric method. Cell viability was determined by the MTT test and trypan blue exclusion test, whereas oxygen consumption was measured by a polarographic technique. After 2 h treatment, NOR-3 induced an increase in the levels of nitric oxide. After 2 h of treatment and 24 h after the end of the treatment with NOR-3, both cell viability and urea synthesis were significantly reduced in comparison to the controls for NOR-3 concentrations equal to or greater than 50 microM. A reduction in oxygen consumption was observed in hepatocytes after 40 min treatment with 100 microM NOR-3, even if the cell viability was unchanged. Reduction of oxygen consumption is an early indicator of the metabolic alterations in hepatocytes exposed to nitric oxide. These findings suggest that nitric oxide accumulation acts on hepatocyte cultures inducing cell death and reduction of urea synthesis after 2 hours.