Objective       To investigate the role of gap junctional intercellular communication in the spasm of ureter of rabbits.       Methods       New Zealand rabbits were randomly divided into control (n=10) and experimental (n=14) group. Ureter spasm animal models were made. Expression and location of Cx43 were detected by Western blotting and immunohistochemical assay. The contraction of ureter strip evoked by minimum electronic stimulus was recorded. Effect of gap junction inhibitor (AGA) on ureter strip contraction was also observed.       Results        There was no obvious diff

erent change in the morphology of the ureter between the 2 groups. Many gap junctions were observed among the ureter smooth muscle cells. Immunohistochemical assay and Western blotting indicated that the expression of Cx43 was enhanced in the experimental than the control groups (

P

0.05). The spontaneous contraction of ureter strip in vitro was observed in the experimental group under the minimum electronic stimulus of 0.42±0.14 mV (

P

0.05). The contraction strength was increased with the increase of electronic stimulus

while the strength of experimental group was stronger than that of control (

P

0.05). AGA significantly inhibited the ureter strip contraction for both groups

with that in the experimental group more significant (

P

0.05).       Conclusion       Cx43-mediated gap junctional intercellular communication is one of important factors for increased excitability and enhanced contraction of the ureter after acute obstruction.