Direct measurement of nitric oxide release from vascular endothelial cells.
A nitric oxide (NO)-selective electrode was used to directly measure NO release from isolated rat aortic endothelium and cultured rat aortic endothelial cells (RAECs). Basal release of NO was significantly attenuated by a NO synthase inhibitor NG-nitro-L-arginine methyl ester (1 mM) to 42 +/- 14 pmol/1 x 10(5) cells (P < 0.01). The basal release of NO was also significantly inhibited by a calmodulin antagonist W-7 at 15 microM (P < 0.01). L-Arginine (1 mM), significantly stimulated NO release (P < 0.05 vs. control basal release). Stimulation of cultured RAECs with two endothelium-dependent vasodilators, acetylcholine (100 nM) and A-23187 (1 microM), significantly increased NO release [574 +/- 112 pmol/1 x 10(5) cells (n = 5) and 658 +/- 119 pmol/1 x 10(5) cells (n = 5) in acetylcholine- and A-23187-stimulated RAECs, respectively]. Basal release of NO was also detectable in isolated rat aortic rings with intact endothelium. NO release was significantly attenuated by NG-nitro-L-arginine methyl ester and augmented by human superoxide dismutase. These data indicate the physiological usefulness of the amperometric measurement of NO employing a NO-specific electrode in biological systems.
Guo
J P
JP
Department of Physiology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Murohara
T
T
Buerke
M
M
Scalia
R
R
Lefer
A M
AM
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D000001:Calcimycin / Q000494:pharmacology; D002138:Calibration; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007202:Indicators and Reagents; D007476:Ionophores / Q000494:pharmacology; D008839:Microelectrodes; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000032:analysis / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010069:Oxadiazoles / Q000494:pharmacology; D051381:Rats; D013449:Sulfonamides / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
C094475:4-hydroxynethyl-furoxan-3-carboxamide; D004791:Enzyme Inhibitors; D007202:Indicators and Reagents; D007476:Ionophores; D010069:Oxadiazoles; D013449:Sulfonamides; D014665:Vasodilator Agents; D009569:Nitric Oxide; D000001:Calcimycin; C017967:W 7; D019001:Nitric Oxide Synthase; D000109:Acetylcholine; D019331:NG-Nitroarginine Methyl Ester