Related Experiment Video
Updated: Jun 8, 2026

Recording of Inward Rectifying K+ Currents in Freshly Isolated Basilar Artery Smooth Muscle Cells by Patch Clamp Technique
Published on: February 7, 2025
Magnesium lithospermate B decreases [Ca(2+)]i in endothelial cells by inhibiting K(+) currents
Haifei Zhang1, Jie Zhang, Ruopeng Zha
1State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
Abstract:
Magnesium lithospermate B (MLB) is a hydrophilic active component of Salviae miltiorrhizae Radix. Studies have shown that MLB affected intracellular calcium ([Ca(2+)]i), but the underlying mechanism was unclear yet. The present work was aimed to investigate the underlying mechanism of MLB affecting [Ca(2+)]i in endothelial cells (ECs). Isolated mesentery arteries were employed to test the involvement of L-Ca(2+) channel. [Ca(2+)]i was measured in ECs loaded with Fluo-3. Membrane potential and membrane currents were recorded in ECs using patch-clamp techniques. Results showed that MLB did not inhibit Ca(2+) influx via L-Ca(2+) channel in isolated mesenteric arteries. However, MLB decreased [Ca(2+)]i in a concentration-dependent manner in ECs. MLB depolarized the membrane potential of ECs and inhibited K(+) currents. These results demonstrated that MLB decreased [Ca(2+)]i by inhibiting K(+) currents and depolarizing membrane potential in ECs.
Related Concept Videos
Antihypertensive Drugs: Action of Calcium Channel Blockers
Antihypertensive Drugs: Vasodilators
Antianginal Drugs: Calcium Channel Blockers and Ranolazine
CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...
Ligand-Gated Ion Channel Receptor: Gating Mechanism
Antihypertensive Drugs: Potassium-Sparing Diuretics
Nitric Oxide Signaling Pathway

