Nitrite uptake and metabolism and oxidant stress in human erythrocytes

• DOI: 10.1152/ajpcell.2000.279.6.c1946
• Publication Date: 2017-12-24T23:05:08Z
• Authors: James M. May; Zhi-Chao Qu; Li Xia; Charles E. Cobb
• Keywords: Methemoglobin; DIDS; Sodium nitrite

Nitric oxide, when released into the bloodstream, is quickly scavenged by Hb in erythrocytes or oxidized to nitrite. Nitrite can also enter and oxidize Hb. The goals of this work were determine mechanism erythrocyte nitrite uptake whether causes oxidant stress these cells. Erythrocytes took up 0.8 mM with a half-time 11 min. was sensitive temperature pH ionic composition medium but not inhibited specific anion-exchange inhibitor DIDS. About 25% occurred on sodium-dependent phosphate transporter rest as diffusion nitrous acid other species across plasma membrane. Methemoglobin formation increased proportion intracellular concentration. reacted ascorbate, ascorbate loading cells decreased nitrite-induced methemoglobin only at high concentrations. In conclusion, rapidly enters reacts oxyhemoglobin does exert strong