MLC1 and irritable bowel syndrome: Evaluation of the intestinal mucosal barrier function revealed that the GP group inhibited the activation of the MLCK/p‐MLC signaling pathway (Figure S6L, Supporting Information), upregulated the expression of intestinal epithelial TJ protein, reduced serum FITC‐dextran levels, and reversed the increase in intestinal permeability of PI‐IBS rats (Figure S6M–P, Supporting Information).