Nitric oxide production by primary liver cells isolated from amino acid diet-fed rats.
Primary mixed liver cells were isolated from rats that had been fed an amino acid (AA) diet in which natural protein was replaced with a defined mixture of pure AAs. Nitric oxide (NO) production from these cells in vitro was monitored using a nitric oxide (NO)-selective fluorescent probe, diaminofluorescein, followed by flow cytometric analysis. High levels of NO fluorescence were seen in approximately half of liver cells isolated from rats fed an AA diet for 1-7 days, whereas there was baseline fluorescence in cells obtained from regular diet-fed rats. The apparent size of NO-producing cells was smaller than those not producing NO. The production of NO was inhibited when rats were treated with either inducible NO synthase (iNOS)- or endothelial NOS-specific inhibitor, and an inhibitor for iNOS induction during AA diet feeding. L-arginine or L-glutamine (material for L-arginine biosynthesis) enriched diet showed the same NO augmentation as in AA diet. It is speculated that a high content of free L-arginine in AA diet may have caused enhanced NO production.
Kotake
Yashige
Y
Oklahoma Medical Research Foundation, Free Radical Biology and Aging Research Program, Oklahoma City, OK 73104, USA.
Kishida
Hideki
H
Nakae
Dai
D
Floyd
Robert A
RA
D000596:Amino Acids / Q000008:administration & dosage*; D000818:Animals; D002478:Cells, Cultured; D004032:Diet; D005434:Flow Cytometry; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009569:Nitric Oxide / Q000096:biosynthesis*; D051381:Rats; D017208:Rats, Wistar
D000596:Amino Acids; D009569:Nitric Oxide