The Underlying Cellular mechanism in the Effect of Ligustrazine on the Anion Secretion of Colonic Mucosa

摘要

Aim: To investigate the underlying cellular mechanism in the effect of ligustrazine on anion secretion of colonic mucosa. Methods: Sheets of rat distal colon were mounted in Ussing chambers and the electrolyte transport was analyzed using short-circuit current (I_(SC)) technique in conjunction with "Tool drugs". Results: (1) In HCO3~--free K-H solution, basolateral application of Immol/L TMP produced an increase in Isc and the total charges transported in 30 minutes was about 8.3 ± 1.9mC/cm~2; Apical pretreatment of DPC(1mmoL/L), the inhibitor of Cl~- channels, decreased the TMP-induced Isc by about 84% (P < 0.01) ; The basolateral presence of bumetanide (0.1mmoL/L), the inhibitor of Na~+-K~+-Cl~- cotransporter (NKCC), significantly reduced the TMP-evoked Isc by about 86% (P < 0.01). (2) In Cl~--free K-H solution, basolateral application of Immol/L TMP produced an increase in Isc and the total charges transported for 30 minutes was about 8.7 ± 1.4mC/cm~2; Apical pretreatment of DPC and basolateral addition of acetazolamide decreased the TMP-induced Isc by about 60% (P < 0.01) and 45%(P < 0.05) respectively; Basolateral application of DIDS, the inhibitor of Na~+-HCO_3~- cotransporter (NBC), didn't alter the TMP-induced Isc. Conclusion: (1) Ligustrazine could promote colonic mucosa secrete Cl~- via apical Cl~- channels and basolateral NKCC. (2) Ligustrazine could promote colonic mucosa secrete HCO_3~- via apical Cl~- channels and basolateral diffusion of CO_2.