Objective: In this research

we studied the TGF-β1 effects on connexin-43 expression in cultured human bladder smooth muscle cells. Methods: Human bladder smooth muscle cells primary cultures

with bladder tissue obtained from patients undergoing cystectomy

were intervened by recombinant human TGF-β1. Connexin-43 expression in human bladder smooth muscle cells was then examined by Western blotting and immunocytochemistry. Results: Stimulation with TGF-β1 led to significant reduction of connexin-43 immunoreactivity and coupling （P<0.0001）. Connexin-43 protein expression was significantly downregulated （P<0.05）. Simultaneously

low phosphorylation species of connexin-43 were particularly affected. Conclusion: Our experiments demonstrated a significant downregulation of connexin-43 by TGF-β1 in cultured human bladder smooth muscle cells. These findings support the view that TGF-β1 is involved in the pathophysiology of urinary bladder dysfunction.