Ondrias Karol, Stasko Andrej, Cacanyiova Sona, Sulova Zdena, Krizanova Olga, Kristek Frantisek, Malekova Lubica, Knezl Vladimir, Breier Albert
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Vlarska 5, 833 34, Bratislava, Slovak Republic.
Pflugers Arch. 2008 Nov;457(2):271-9. doi: 10.1007/s00424-008-0519-0. Epub 2008 May 6.
Nitrosoglutathione [(GSNO), 500 nmol/l] relaxed the norepinephrine precontracted rat aortic rings. The relaxation effect was pronouncedly enhanced by H(2)S- and HS(-)-donor NaHS (30 micromol/l) at 7.5 pH but not at 6.3 pH. To study molecular mechanism of this effect, we investigated whether NaHS can release NO from NO donors. Using an electron paramagnetic resonance spectroscopy method of spin trap and by measuring the NO oxidation product, which is nitrite, by the Griess reaction, we report that NaHS released NO from nitrosothiols, namely from GSNO, S-nitroso-N-acetyl-DL: -penicillamine (SNAP), from metal nitrosyl complex nitroprusside (SNP) and from rat brain homogenate and murine L1210 leukaemia cells. From the observation that the releasing effect was more pronounced at 8.0 pH than 6.0 pH, we suppose that HS(-), rather than H(2)S, is responsible for the NO-releasing effect. Since in mammals, H(2)S and HS(-) are produced endogenously, we assume that their effect to release NO from nitrosothiols and from metal nitrosyl complexes are responsible for some of their biological activities and that this mechanism may be involved in S-nitrosothiol-signalling reactions.
亚硝基谷胱甘肽[（GSNO），500纳摩尔/升]可使去甲肾上腺素预收缩的大鼠主动脉环舒张。在pH值为7.5时，H₂S和HS⁻供体硫氢化钠（30微摩尔/升）可显著增强这种舒张作用，但在pH值为6.3时则不然。为研究这种作用的分子机制，我们研究了硫氢化钠是否能从一氧化氮供体中释放一氧化氮。通过自旋捕集的电子顺磁共振波谱法并利用格里斯反应测量一氧化氮氧化产物亚硝酸盐，我们报告硫氢化钠可从亚硝基硫醇中释放一氧化氮，即从GSNO、S-亚硝基-N-乙酰-DL-青霉胺（SNAP）、金属亚硝基络合物硝普钠（SNP）以及大鼠脑匀浆和小鼠L1210白血病细胞中释放。从释放作用在pH值为8.0时比在pH值为6.0时更明显这一观察结果，我们推测是HS⁻而非H₂S负责一氧化氮释放作用。由于在哺乳动物体内，H₂S和HS⁻是内源性产生的，我们假设它们从亚硝基硫醇和金属亚硝基络合物中释放一氧化氮的作用是其某些生物学活性的原因，并且这种机制可能参与亚硝基硫醇信号反应。
