Voltage-gated potassium channels are involved in oxymatrine-regulated islet function in rat islet β cells and INS-1 cells

Document Type : Original Article


1 Department of Pediatrics, Shanxi Medical University, Taiyuan, China

2 Pediatric internal Medicine, Children’s Hospital of Shanxi Province, Shanxi Medical University, Taiyuan, China


Objective(s): Oxymatrine can regulate glucose metabolism. But the underlying mechanisms remain unclear. We investigated the relationship of oxymatrine and voltage-gated potassium (Kv) channel in rat islet β cells and INS-1 cells.
Materials and Methods: Insulin secretion and Kv channel currents were tested by radioimmunoassay and patch-clamp technique, respectively. The INS-1 cell viability was detected using cell counting kit-8 experiments. Flowcytometry analysis and western blot were employed for cell apoptosis and protein levels, respectively. INS-1 cell proliferation was assessed by the 5-Ethynyl-2’- deoxyuridine method.
Results: Oxymatrine potentiated insulin secretion at high glucose (p Conclusion: The results indicate that oxymatrine can stimulate insulin secretion and decrease kv channel currents in islet β cells. Besides, oxymatrine also increases cell viability, proliferation, and reduces cell apoptosis in INS-1 cells. The effects of oxymatrine are related to kv channels. This finding provides new insight into the mechanisms of oxymatrine-regulated islet function.


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