血管活性物质对猪冠状动脉的作用

目的：研究乙酰胆碱(Ach)、硝普钠(SNP)和CPU-86017等血管活性物质对猪冠状动脉的作用及其机制。方法：观察在高钾环境下Ach对冠状动脉环张力的作用及N-硝基精氨酸(LNNA)、血红蛋白(Hb)、亚甲蓝(MB)、吲哚美辛或格列苯脲对其的影响；同时也观察了SNP的作用及在无钙和有钙环境下CPU-86017对高钾引起冠状动脉收缩的影响。结果：Ach在高钾环境下刺激血管进一步收缩。L-NNA在Ach低浓度时能加强血管收缩，而Hb、MB、吲哚美辛和格列苯脲没有此明显作用。在无钙环境下，CPU-86017可显著抑制高钾引起的冠脉收缩，而对复钙所致的进一步收缩仅有抑制趋势，无统计学意义。结论：NO和KCa通道对冠状动脉舒缩调节具有重要意义。CPU-86017能显著抑制高钾引起的冠状动脉收缩，并主要作用于胞内钙库动员所致收缩的部分。

Effects of Arterial Active Substances on Porcine Coronary Arteries

Objective:To investigate the effects and mechanisms of acetylcholine (Ach), sodium nitroprussid (SNP) and CPU-86017 on porcine coronary arteries. Methods:Cumulative concentration-response curves of Ach were investigated with or without N-nitro-L-Arginine(L-NNA), Hemoglobin (Hb), Methylene Blue (MB), Indomethacin, or Glibenclamide on coronary artery rings precontracted by high K+. The effect of SNP was also observed in high K+ physiological salt solution (PSS). The effects of CPU-86017 on the contraction induced by KCl were detected in Ca ++-free PSS followed with restoration of Ca ++. Results:Ach induced apparent contraction in presence of high K+, which was enhanced at low concentration by L-NNA, but not affected by MB, Hb, Indomethacin, and Glibenclamide. The concentration-respond curve of SNP was rightward shifted by high K+. CPU-86017 significantly inhibited the contractions induced by high K+ in Ca ++ free PSS. However, there was no statistically significant inhibition by the following application of Ca ++ due to the big variation of the data. Conclusions:NO and K Ca channel play important roles in modulating the tone of coronary arteries. CPU-86017 possesses a potant inhibition on the contraction induced by high K+ on coronary arteries, especially on the component of intracellular Ca ++ mobilization.