Potassium Channels Contributes to Apelin-induced Vasodilation in Rat Thoracic Aorta

Sahinturk S., Demirel S., Isbil N., Ozyener F.

PROTEIN AND PEPTIDE LETTERS, vol.29, no.6, pp.538-549, 2022 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 29 Issue: 6
  • Publication Date: 2022
  • Doi Number: 10.2174/0929866529666220516141317
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, EMBASE, MEDLINE
  • Page Numbers: pp.538-549
  • Keywords: Apelin, potassium channels, thoracic aorta, tissue bath, vasorelaxation, endogenous, NITRIC-OXIDE, PHYSIOLOGICAL ROLES, BLOOD-PRESSURE, ION CHANNELS, ARTERIES, APJ, MECHANISMS, RECEPTOR, ISOFORM
  • Bursa Uludag University Affiliated: Yes


Background: Apelin is a newly discovered peptide hormone and originally discovered endogenous apelin receptor ligand. Objective: In this study, we aimed to investigate the possible roles of potassium channel subtypes in the vasorelaxant effect mechanisms of apelin. Methods: The vascular rings obtained from the thoracic aortas of the male Wistar Albino rats were placed into the isolated tissue bath system. The resting tension was set to 2 g. After the equilibration period, the aortic rings were precontracted with 10-5 M phenylephrine (PHE) or 45 mM KCl. Pyroglutamyl-apelin-13 ([Pyr1]apelin-13), which is the dominant apelin isoform in the human cardiovascular tissues and human plasma, was applied cumulatively (10(-10)-10(-6) M) to the aortic rings in the plateau phase. The experimental protocol was repeated in the presence of specific K+ channel subtype blockers to determine the role of K(+)channels in the vasorelaxant effect mechanisms of apelin. Results: [Pyr1]apelin-13 induced a concentration-dependent vasorelaxation (p < 0.001). The maximum relaxation level was approximately 52%, according to PHE-induced contraction. Tetraethylammonium, iberiotoxin, 4-Aminopyridine, glyburide, anandamide, and BaCl2 statistically significantly decreased the vasorelaxant effect level of [Pyr1]apelin-13 (p < 0.001). However, apamin didn't statistically significantly change the vasorelaxant effect level of [Pyr1]apelin-13. Conclusion: In conclusion, our findings suggest that BKCa, IKCa, Kv, K-ATP, Kir, and K-2P channels are involved in the vasorelaxant effect mechanisms of apelin in the rat thoracic aorta.