摘要：The present study investigated the effect of ferulic acid, a compound purified from traditional Chinese herbal medicine Chuanxiong and Awei , on anion secretion by human colonic cells (T84) using the short circuit current ( I SC) and microspectrofluorimetric technique. Basolateral administration of sodium ferulate (SF) produced a concentration-dependent increase of I SC in T84 cells with an EC50 of 1.2 m M . The SF-induced increase in I SC contained a transient peak followed by a sustained plateau. Removal of extracellular Cl−, basolateral addition of bumetanide, an inhibitor of the Na+–K+–Cl− cotransporter (NKCC) and apical pretreatment with DPC, a Cl− channels blocker, decreased the SF-induced increase in I SC by 94% ( p <0.001), 84% ( p <0.001) and 85% ( p <0.001) respectively. Pretreatment with thapsigargin, a specific microsomal Ca2+-ATPase inhibitor, in combination with EGTA, a Ca2+ chelator, decreased the SF-induced peak by 52% ( p <0.01) and inhibited the SF-induced plateau by 60% ( p <0.05). Pretreatment with MDL12330A, an adenylate cyclase inhibitor, blocked the SF-induced I SC plateau by 87% ( p <0.01) but did not affect the SF-induced I SC peak. Microspectrofluorimetric measurements show that SF induced a sustained increase in [Ca2+]i. The results suggested that SF could induce Cl− secretion in T84 cells via Ca2+ and cAMP-dependent pathways.
