| 8945906 |
Goda N, Suematsu M, Mukai M, Kiyokawa K, Natori M, Nozawa S, Ishimura Y: Modulation of mitochondrion-mediated oxidative stress by nitric oxide in human placental trophoblastic cells. Oncogene. 1998 Nov 12;17(19):2515-24.
Intracellular hydroperoxide generation in cultured human placental trophoblastic cells (HPTCs) was quantitatively monitored in the presence or absence of an NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 1 mM), by digital microfluorography with use of carboxydichlorofluorescein, a hydroperoxide-sensitive fluorogenic probe. In the absence of L-NAME, HPTCs displayed a time-dependent gradual elevation of the fluorescence, suggesting the ability to produce oxidants spontaneously. In the presence of L-NAME, however, the fluorescent response in these cells increased further; the oxidative impact elicited by L-NAME treatment for 30 min was equivalent to that induced by application of 230 microM tert-butyl hydroperoxide for 5 min. This oxidative process was completely blocked by rotenone, a reagent that interferes with electron entry into complex I of the mitochondrial respiratory chain. On the other hand, antimycin A, which blocks mitochondria at the distal site of the ubiquinone pool, potentiated the L-NAME-induced oxidative change. These findings suggest that constitutive levels of nitric oxide production contribute to regulation of mitochondrion-derived intracellular oxidant generation in HPTCs. |
81(1,1,1,1) |