Wang R, Ghahary A, Shen Y J, Scott P G, Tredget E E
Department of Surgery, University of Alberta, Edmonton, Canada.
J Invest Dermatol. 1996 Mar;106(3):419-27. doi: 10.1111/1523-1747.ep12343428.
Nitric oxide (NO) is produced by a variety of human and animal cells and is involved in a broad array of physiological and pathophysiological processes. It can cause vasodilation, serve as a neurotransmitter, and have anti-neoplastic, anti-microbial, and anti-proliferative effects. In this study, we have demonstrated that fibroblasts derived from human skin spontaneously produce NO and that this production can be enhanced by stimulating the cells with interferon-gamma and lipopolysaccharide. The production of NO by human dermal fibroblasts can be blocked by NG-monomethyl-L-arginine (L-NMMA). The inhibitory effect of L-NMMA on NO production was restored by addition of L-arginine but not D-arginine. By measuring the rate of conversion of [14C]L-arginine to [14C]L-citrulline, we show that unstimulated cells expressed only Ca2+-dependent NO synthase (NOS) activity (1.36 +/- 0.57 pmol/mg/min; n = 4) whereas stimulated cells expressed both Ca2+-dependent (2.60 +/- 0.54 pmol/mg/min; n = 4) and -independent (1.59 +/- 0.14 pmol/mg/min; n = 4) NOS activities. With reverse transcription polymerase chain reaction (RT-PCR), the 422-bp RT-PCR product for human endothelial constitutive NOS and the 462-bp RT-PCR product for human hepatocyte inducible NOS were detected in proportion to the amount of mRNA-related RT-cDNA added to the reaction mixture. Further evidence by immunocytochemistry demonstrated that human dermal fibroblasts express both constitutive and inducible NOS proteins. These data collectively suggest that in addition to macrophages and other inflammatory cells, nitric oxide production by dermal fibroblasts could be important during the inflammatory stages of wound healing and possibly also in the later stages of proliferation and tissue remodeling after skin injury in humans.
一氧化氮（NO）由多种人类和动物细胞产生，并参与广泛的生理和病理生理过程。它可引起血管舒张，充当神经递质，并具有抗肿瘤、抗微生物和抗增殖作用。在本研究中，我们证明了源自人皮肤的成纤维细胞可自发产生NO，并且通过用γ干扰素和脂多糖刺激细胞可增强这种产生。人真皮成纤维细胞产生的NO可被NG-单甲基-L-精氨酸（L-NMMA）阻断。添加L-精氨酸可恢复L-NMMA对NO产生的抑制作用，但添加D-精氨酸则不能。通过测量[14C]L-精氨酸向[14C]L-瓜氨酸的转化速率，我们发现未刺激的细胞仅表达钙依赖性一氧化氮合酶（NOS）活性（1.36±0.57 pmol/mg/min；n = 4），而刺激的细胞则同时表达钙依赖性（2.60±0.54 pmol/mg/min；n = 4）和非钙依赖性（1.59±0.14 pmol/mg/min；n = 4）NOS活性。通过逆转录聚合酶链反应（RT-PCR），与添加到反应混合物中的mRNA相关RT-cDNA量成比例地检测到了人内皮组成型NOS的422 bp RT-PCR产物和人肝细胞诱导型NOS的462 bp RT-PCR产物。免疫细胞化学的进一步证据表明，人真皮成纤维细胞表达组成型和诱导型NOS蛋白。这些数据共同表明，除了巨噬细胞和其他炎症细胞外，真皮成纤维细胞产生一氧化氮在伤口愈合的炎症阶段可能很重要，在人类皮肤损伤后的增殖和组织重塑后期也可能很重要。
