Dalaklioglu Selvinaz, Ozbey G
Department of Pharmacology, Akdeniz University, Medical Faculty, 07070, Antalya, Turkey.
Pharmacogn Mag. 2014 Jan;10(37):47-52. doi: 10.4103/0973-1296.126658.
Resveratrol (RVT), one of the most commonly employed dietary polyphenol, is used in traditional Japanese and Chinese medicine for treatment of cardiovascular diseases. Recently, we have shown that RVT has a potent relaxant effect on rat corpus cavernosum via endothelium-dependent and -independent mechanisms.
The present study addressed the question whether different types of potassium channels are involved in the endothelium-dependent and -independent mechanism of corpus cavernosum relaxation induced by RVT.
Strips of corpus cavernosum from rats were mounted in an organ-bath system for isometric tension studies.
RVT (1-100 μmol/L) produced concentration-dependent relaxation responses in rat corpus cavernosum pre-contracted by phenylephrine. The non-selective potassium channels blocker tetraethylammonium chloride (TEA, 10 mmol/L), ATP-sensitive potassium (KATP) channels blocker glibenclamide (10 μmol/L), and inward rectifier potassium (Kir) channels inhibitor barium chloride (BaCl2, 30 μmol/L) caused a significant inhibition on the relaxation response to RVT, whereas voltage-dependent potassium channels inhibitor 4-aminopyridine (4-AP, 1 mmol/L), and large conductance calcium-activated potassium (BKCa) channels inhibitor iberiotoxin (IbTX, 0.1 μmol/L) did not significantly alter relaxant responses of corpus cavernosum strips to RVT. In addition, relaxant responses to RVT did not significantly inhibited by the combination of selective inhibitors of small and intermediate conductance BKCa channels (0.1 μmol/L charybdotoxin and 1 μmol/L apamin, respectively).
These results demonstrated that endothelial small and intermediate conductance BKCa channels are not thought to be an important role in RVT-induced endothelium-dependent relaxation of corpus cavernosum. The endothelium-independent corpus cavernosum relaxation induced by RVT is seems to largely depend on Kir channels and KATP channels in corporal tissue.
白藜芦醇（RVT）是最常用的膳食多酚之一，在传统日本和中医中用于治疗心血管疾病。最近，我们已经表明，RVT通过内皮依赖性和非依赖性机制对大鼠海绵体具有强大的舒张作用。
本研究探讨了不同类型的钾通道是否参与RVT诱导的海绵体舒张的内皮依赖性和非依赖性机制。
将大鼠海绵体条带安装在器官浴系统中进行等长张力研究。
RVT（1-100μmol/L）对去氧肾上腺素预收缩的大鼠海绵体产生浓度依赖性舒张反应。非选择性钾通道阻滞剂氯化四乙铵（TEA，10mmol/L）、ATP敏感性钾（KATP）通道阻滞剂格列本脲（10μmol/L）和内向整流钾（Kir）通道抑制剂氯化钡（BaCl2，30μmol/L）对RVT的舒张反应产生显著抑制，而电压依赖性钾通道抑制剂4-氨基吡啶（4-AP，1mmol/L）和大电导钙激活钾（BKCa）通道抑制剂iberiotoxin（IbTX，0.1μmol/L）并未显著改变海绵体条带对RVT的舒张反应。此外，小电导和中电导BKCa通道的选择性抑制剂（分别为0.1μmol/L的蝎毒素和1μmol/L的蜂毒明肽）联合使用对RVT的舒张反应没有显著抑制作用。
这些结果表明，内皮小电导和中电导BKCa通道在RVT诱导的海绵体内皮依赖性舒张中似乎不起重要作用。RVT诱导的海绵体非内皮依赖性舒张似乎在很大程度上取决于海绵体组织中的Kir通道和KATP通道。
