eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2026-06-19 19 2 72344 article Sardor Bakhtiyor ugli Sobirov 1 Abdisalim Abdikarimovich Zaripov 1 Inoyat Zulfiqorovich Zhumaev 1 Pulat Bekmuratovich Usmanov 1 Adilbay Tlepovich Esimbetov 1 Shavkat Yusubovich Rustamov 1 Department of Cell Biophysics, Institute of Biophysics and Biochemistry, National University of Uzbekistan, Tashkent, Uzbekistan Department of Alkaloids Chemistry,Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent, Uzbekistan Department of Animal Anatomy and Physiology, Karakalpak State University named after Berdakh, Nukus, Uzbekistan Department of Medical and Biological Sciences, Uzbek State University of Physical Education and Sports, Chirchiq, Uzbekistan Department of Physiology and Pathology, Tashkent State Medical University, Tashkent, Uzbekistan This study aims to evaluate how plasma membrane calcium transport mechanisms—specifically L-type calcium channels, receptor-operated calcium channels, and the sodium-calcium exchanger—contribute to the vasorelaxant activity of the alkaloid CAM-68. The isometric contraction force of the aortic rings was recorded using a Grass-Telefactor FT.03 myograph and analysed with the PowerLab data-acquisition software (ADInstruments). Findings indicate that the alkaloid CAM-68 exerts an effective vasorelaxant effect on vascular smooth muscle, which is primarily achieved by modulating intracellular Ca²⁺ concentration.The CAM-68 alkaloid inhibits voltage-dependent L-type Ca²⁺ channels and receptor-operated Ca²⁺ channels in the plasma membrane. It also attenuates the activity of the Na⁺/Ca²⁺ exchange in reverse mode. These effects are associated with the modulation of smooth muscle cell Ca²⁺ homeostasis and the attenuation of Ca²⁺ influx across the membrane. https://biomedpharmajournal.org/vol19no2/evaluation-of-the-role-of-plasmalemma-ca%c2%b2%e2%81%ba-transport-systems-in-the-vasorelaxant-effect-of-the-cam-68-alkaloid-under-in-vitro-conditions/ Alakaloid L-type Ca²⁺-channels Na⁺/Ca²⁺ exchange Ouabain Smooth muscle