Abstract：
OBJECTIVE: The treatment of cardiovascular diseases (CVD) could greatly benefit from using nitric oxide (NO) donors. This study aimed to investigate the mechanisms of action of NONO2P that contribute to the observed responses in the mesenteric artery. The hypothesis was that NONO2P would have similar pharmacological actions to sodium nitroprusside (SNP) and NO.
METHODS: Male Wistar rats were euthanized to isolate the superior mesenteric artery for isometric tension recordings. NO levels were measured using the DAF-FM/DA dye, and cyclic guanosine monophosphate (cGMP) levels were determined using a cGMP-ELISA Kit.
RESULTS: NONO2P presented a similar maximum efficacy to SNP. The free radical of NO (NO•) scavengers (PTIO; 100 μM and hydroxocobalamin; 30 μM) and nitroxyl anion (NO-) scavenger (L-cysteine; 3 mM) decreased relaxations promoted by NONO2P. The presence of the specific soluble guanylyl cyclase (sGC) inhibitor (ODQ; 10 μM) nearly abolished the vasorelaxation. The cGMP-dependent protein kinase (PKG) inhibition (KT5823; 1 μM) attenuated the NONO2P relaxant effect. The vasorelaxant response was significantly attenuated by blocking inward rectifying K+ channels (Kir), voltage-operated K+ channels (KV), and large conductance Ca2+-activated K+ channels (BKCa). NONO2P-induced relaxation was attenuated by cyclopiazonic acid (10 μM), indicating that sarcoplasmic reticulum Ca2+-ATPase (SERCA) activation is involved in this relaxation. Moreover, NONO2P increased NO levels in endothelial cells and cGMP production.
CONCLUSIONS: NONO2P induces vasorelaxation with the same magnitude as SNP, releasing NO• and NO-. Its vasorelaxant effect involves sGC, PKG, K+ channels opening, and SERCA activation, suggesting its potential as a therapeutic option for CVD.
METHODS: Male Wistar rats were euthanized to isolate the superior mesenteric artery for isometric tension recordings. NO levels were measured using the DAF-FM/DA dye, and cyclic guanosine monophosphate (cGMP) levels were determined using a cGMP-ELISA Kit.
RESULTS: NONO2P presented a similar maximum efficacy to SNP. The free radical of NO (NO•) scavengers (PTIO; 100 μM and hydroxocobalamin; 30 μM) and nitroxyl anion (NO-) scavenger (L-cysteine; 3 mM) decreased relaxations promoted by NONO2P. The presence of the specific soluble guanylyl cyclase (sGC) inhibitor (ODQ; 10 μM) nearly abolished the vasorelaxation. The cGMP-dependent protein kinase (PKG) inhibition (KT5823; 1 μM) attenuated the NONO2P relaxant effect. The vasorelaxant response was significantly attenuated by blocking inward rectifying K+ channels (Kir), voltage-operated K+ channels (KV), and large conductance Ca2+-activated K+ channels (BKCa). NONO2P-induced relaxation was attenuated by cyclopiazonic acid (10 μM), indicating that sarcoplasmic reticulum Ca2+-ATPase (SERCA) activation is involved in this relaxation. Moreover, NONO2P increased NO levels in endothelial cells and cGMP production.
CONCLUSIONS: NONO2P induces vasorelaxation with the same magnitude as SNP, releasing NO• and NO-. Its vasorelaxant effect involves sGC, PKG, K+ channels opening, and SERCA activation, suggesting its potential as a therapeutic option for CVD.
摘要：
目的：使用一氧化氮（NO）供体可以极大地受益于心血管疾病（CVD）的治疗。这项研究旨在研究NONONO2P的作用机制，该机制有助于在肠系膜动脉中观察到的反应。假设NONO2P与硝普钠（SNP）和NO具有相似的药理作用。
方法:对雄性Wistar大鼠实施安乐死以分离肠系膜上动脉以进行等距张力记录。使用DAF-FM/DA染料测量NO水平，使用cGMP-ELISA试剂盒测定环磷酸鸟苷(cGMP)水平。
结果：NONO2P表现出与SNP相似的最大功效。NO（NO•）清除剂（PTIO；100μM和羟钴胺素；30μM）和硝酰基阴离子（NO-）清除剂（L-半胱氨酸；3mM）的自由基降低了NONO2P促进的弛豫。特异性可溶性鸟苷酸环化酶（sGC）抑制剂（ODQ;10μM）的存在几乎消除了血管舒张。cGMP依赖性蛋白激酶(PKG)抑制(KT5823;1μM)减弱NONO2P松弛作用。通过阻断内向整流K通道（Kir），血管松弛反应显着减弱，电压操作K+通道（KV），大电导Ca2+激活K+通道(BKCa)。环吡嗪酸（10μM）减弱了NONO2P诱导的弛豫，表明肌浆网Ca2-ATPase（SERCA）激活参与了这种松弛。此外，NONO2P增加内皮细胞中的NO水平和cGMP产生。
结论：NONO2P诱导血管舒张的幅度与SNP相同，释放NO•和NO-。它的血管舒张作用涉及sGC，PKG,K+通道打开,和SERCA激活，提示其作为心血管疾病治疗选择的潜力。
方法:对雄性Wistar大鼠实施安乐死以分离肠系膜上动脉以进行等距张力记录。使用DAF-FM/DA染料测量NO水平，使用cGMP-ELISA试剂盒测定环磷酸鸟苷(cGMP)水平。
结果：NONO2P表现出与SNP相似的最大功效。NO（NO•）清除剂（PTIO；100μM和羟钴胺素；30μM）和硝酰基阴离子（NO-）清除剂（L-半胱氨酸；3mM）的自由基降低了NONO2P促进的弛豫。特异性可溶性鸟苷酸环化酶（sGC）抑制剂（ODQ;10μM）的存在几乎消除了血管舒张。cGMP依赖性蛋白激酶(PKG)抑制(KT5823;1μM)减弱NONO2P松弛作用。通过阻断内向整流K通道（Kir），血管松弛反应显着减弱，电压操作K+通道（KV），大电导Ca2+激活K+通道(BKCa)。环吡嗪酸（10μM）减弱了NONO2P诱导的弛豫，表明肌浆网Ca2-ATPase（SERCA）激活参与了这种松弛。此外，NONO2P增加内皮细胞中的NO水平和cGMP产生。
结论：NONO2P诱导血管舒张的幅度与SNP相同，释放NO•和NO-。它的血管舒张作用涉及sGC，PKG,K+通道打开,和SERCA激活，提示其作为心血管疾病治疗选择的潜力。
