TRPV3 is a Ca²⁺-permeable cation channel, prominently expressed by keratinocytes where it contributes to maintaining the skin barrier, skin regeneration, and keratinocyte differentiation. However, much less is known about its physiological function in other tissues and there is still a need for identifying novel and efficient TRPV3 channel blockers. By screening a compound library, we identified 26E01 as a novel TRPV3 blocker. 26E01 blocks heterologously expressed TRPV3 channels overexpressed in HEK293 cells as assessed by fluorometric intracellular free Ca²⁺ assays (IC₅₀ = 8.6 μM) but does not affect TRPV1, TRPV2 or TRPV4 channels. Electrophysiological whole-cell recordings confirmed the reversible block of TRPV3 currents by 26E01, which was also effective in excised inside-out patches, hinting to a rather direct mode of action. 26E01 suppresses endogenous TRPV3 currents in the mouse 308 keratinocyte cell line and in the human DLD-1 colon carcinoma cell line (IC₅₀ = 12 μM). In sections of the gastrointestinal epithelium of mice, the expression of TRPV3 mRNA follows a gradient along the gastrointestinal tract, with the highest expression in the distal colon. 26E01 efficiently attenuates 2-aminoethoxydiphenyl borate-induced calcium influx in primary colonic epithelial cells isolated from the distal colon. As 26E01 neither shows toxic effects on DLD-1 cells at concentrations of up to 100 μM in MTT assays nor on mouse primary colonic crypts as assessed by calcein-AM/propidium iodide co-staining, it may serve as a useful tool to further study the physiological function of TRPV3 in various tissues.

TRPV3 是一种 Ca ²⁺可渗透的阳离子通道，主要由角质形成细胞表达，在那里它有助于维持皮肤屏障、皮肤再生和角质形成细胞分化。然而，对其在其他组织中的生理功能知之甚少，仍然需要识别新型有效的 TRPV3 通道阻滞剂。通过筛选化合物库，我们将 26E01 鉴定为新型 TRPV3 阻滞剂。根据荧光细胞内游离 Ca ²⁺测定 (IC ₅₀ = 8.6 μM）但不影响 TRPV1、TRPV2 或 TRPV4 通道。电生理全细胞记录证实了 26E01 对 TRPV3 电流的可逆阻断，这对切除的由内而外的斑块也有效，暗示了一种相当直接的作用模式。26E01 抑制小鼠 308 角质形成细胞系和人 DLD-1 结肠癌细胞系中的内源性 TRPV3 电流 (IC ₅₀ = 12 微米）。在小鼠胃肠道上皮切片中，TRPV3 mRNA 的表达沿胃肠道呈梯度变化，在远端结肠中表达最高。26E01 可有效减弱 2-氨基乙氧基二苯基硼酸盐诱导的从远端结肠分离的原代结肠上皮细胞中的钙流入。由于 26E01 在 MTT 测定中浓度高达 100 μM 时对 DLD-1 细胞和通过钙黄绿素-AM/碘化丙啶共染色评估的小鼠原代结肠隐窝均未显示出毒性作用，因此它可以作为进一步研究的有用工具TRPV3在各种组织中的生理功能。