Oh, Soo-Jin Park, Jung Hwan Han, Sungyu Lee, Jae Kyun Roh, Eun Joo Lee, C. Justin 2024-01-20T22:34:27Z 2024-01-20T22:34:27Z 2021-09-02 2008-10 1756-6606 https://pubs.kist.re.kr/handle/201004/133130 Background: Ca2+-activated Cl- channels (CaCCs) participate in many important physiological processes. However, the lack of effective and selective blockers has hindered the study of these channels, mostly due to the lack of good assay system. Here, we have developed a reliable drug screening method for better blockers of CaCCs, using the endogeneous CaCCs in Xenopus laevis oocytes and two-electrode voltage-clamp (TEVC) technique. Results: Oocytes were prepared with a treatment of Ca2+ ionophore, which was followed by a treatment of thapsigargin which depletes Ca2+ stores to eliminate any contribution of Ca2+ release. TEVC was performed with micropipette containing chelerythrine to prevent PKC dependent run-up or run-down. Under these conditions, Ca2+-activated Cl- currents induced by bath application of Ca2+ to oocytes showed stable peak amplitude when repetitively activated, allowing us to test several concentrations of a test compound from one oocyte. Inhibitory activities of commercially available blockers and synthesized anthranilic acid derivatives were tested using this method. As a result, newly synthesized N-(4-trifluoromethylphenyl)anthranilic acid with trifluoromethyl group (-CF3) at para position on the benzene ring showed the lowest IC50. Conclusion: Our results provide an optimal drug screening strategy suitable for high throughput screening, and propose N-(4-trifluoromethylphenyl) anthranilic acid as an improved CaCC blocker. English BMC Development of selective blockers for Ca2+-activated Cl- channel using Xenopus laevis oocytes with an improved drug screening strategy Article 10.1186/1756-6606-1-14 1 MOLECULAR BRAIN, v.1 MOLECULAR BRAIN 1 scie scopus 000208457000014 2-s2.0-79955711439 Neurosciences Neurosciences & Neurology Article