The Role of Kv7.1-7.5 Channels in Apela-induced Vasorelaxation in the Rat Thoracic Aorta

Öz

Apela is a recently discovered hormonal peptide. This study aimed to investigate the roles of Kv7.1-7.5 channels in the vasorelaxant effects of Apela in a rat thoracic aortic model. The 4 mm thoracic aortic rings isolated from the male Wistar Albino rats were placed in the bath chambers in the isolated tissue bath system. The resting tension level was adjusted to 1 gram. After the 90 min equilibration period, the thoracic aortic rings were contracted with phenylephrine or potassium chloride. Once a stable contraction was achieved, Apela (10-10-10-6 M) was administered cumulatively to the thoracic aortic rings. To reveal the mechanisms of action of Apela, the specified experimental protocol was repeated in the presence of the selective Kv7.1-7.5 channel blocker (XE-991; 30 µM). Apela showed a significant vasodilatory effect in a concentration-dependent manner (p<0.001). The vasorelaxant effect of Apela was largely preserved after the removal of the endothelium. Apela’s vasodilatory effect level was statistically significantly reduced (p<0.001) after administration of the selective Kv7.1-7.5 channel blocker XE-991 in the thoracic aortic rings of rats with intact or denuded endothelium. In conclusion, Kv7.1-7.5 channels contribute to the vasorelaxant effect mechanisms of Apela.

Anahtar Kelimeler

• Apela
• Endothelium
• Potassium
• Vasodilation

Kv7.1-7.5 Kanallarının Sıçan Torasik Aortundaki Apela Kaynaklı Vasorelaksasyondaki Rolü

Öz

Apela yeni keşfedilen bir hormonal peptiddir. Bu çalışma, Apela'nın damar gevşetici etkilerinde Kv7.1-7.5 kanallarının rolünü sıçan torasik aort modelinde araştırmayı amaçladı. Erkek Wistar Albino sıçanlardan izole edilen 4 mm’lik torasik aort halkaları izole doku banyosu sistemindeki banyo haznelerine yerleştirildi. Dinlenim durumundaki gerim seviyesi 1 gram olarak ayarlandı. 90 dakikalık dengelenme periyodundan sonra, torasik aort halkaları fenilefrin veya potasyum klorür ile kasıldı. Stabil bir kasılma sağlandıktan sonra torasik aort halkalarına kümülatif olarak Apela (10-10-10-6 M) uygulandı. Apela'nın etki mekanizmalarını ortaya koymak için, belirtilen deney protokolü, seçici Kv7.1-7.5 kanal blokörü (XE-991; 30 µM) varlığında tekrarlandı. Apela, konsantrasyona bağlı olarak anlamlı düzeyde damar gevşetici etki gösterdi (p<0,001). Apela'nın damar gevşetici etkisi endotelin çıkarılmasından sonra büyük ölçüde korundu. Apela'nın vazodilatör etki seviyesi sağlam veya çıkarılmış endoteli olan sıçan torasik aort halkalarına seçici Kv7.1-7.5 kanal blokeri XE-991 uygulanmasından sonra istatistiksel olarak anlamlı ölçüde azaldı (p<0,001). Sonuç olarak, Kv7.1-7.5 kanalları Apela'nın damar gevşetici etki mekanizmalarına katkıda bulunmaktadır.

Anahtar Kelimeler

• Apela
• Endotel
• Potasyum
• Vazodilatasyon

Kaynakça

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