eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2024-03-20 17 1 483 491 10.13005/bpj/2876 57216 article Yulduzkhon T. Mirzayeva 1 Abdisalim A. Zaripov 1 Inoyat Z. Zhumaev 1 Pulat B. Usmanov 1 Shavkat Yu. Rustamov 1 Sadriddin N. Boboev 1 Institute of Biophysics and Biochemistry et the National University of Uzbekistan, Tashkent, Uzbekistan Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent, Uzbekistan Introduction: Using conventional organ bath procedures, the current study sought to determine how vincanine hydrochloride affected vasorelaxation brought on by hypoxia in rat aortic rings. Methods: To induce hypoxia, we used a glucose-free Krebs solution that was infused with 95% N₂ and 5% CO₂. After 60 minutes of hypoxia, the effect of vincanine was evaluated on aortic rings that were precontracted with either 50 mM KCl or 1 µM phenylephrine (PE). The effect of vincanine was more noticeable in aortic rings that had been precontracted by PE as opposed to KCl. Additionally, when verapamil, a blocker of L-type VDCCs, was preincubated with endothelium-intact aortic rings and KCI was used for precontraction, the effect of vincanine on hypoxia-induced vasorelaxation was significantly reduced. Results: Vincanine inhibited hypoxia-induced vasorelaxation in aortic rings precontracted with PE in a calcium-free buffer. Furthermore, the presence of glibenclamide, a specific inhibitor of ATP-sensitive K⁺-channels (K_ATP), and tetraethylammonium chloride (TEA), a nonspecific inhibitor of calcium-activated large conductance K⁺-channels (BKca), significantly reduced the effect of vincanine on hypoxia-induced vasorelaxation. The removal of the endothelium also had a significant impact on the effect of vincanine on hypoxia-induced vasorelaxation. Conclusion: The present findings showed that alkaloid vincanine isolated from the leaves of Vinca minor H. significantly abolished the hypoxia-induced vasorelaxation in rat aorta. The obtained results suggest that vincanine may protect the rat aorta against hypoxic injuries in the vasculature. https://biomedpharmajournal.org/vol17no1/the-protective-effect-of-indole-alkaloid-vincanine-against-hypoxia-induced-vasorelaxation-model-of-rat-aorta/ Hypoxia Rat Aorta Vasorelaxation Vincanine