Upregulation of RGS4 and downregulation of CPI-17 mediate inhibition of colonic muscle contraction by interleukin-1beta.

ABSTRACT: The pro-inflammatory cytokine IL-1beta contributes to the reduced contractile responses of gut smooth muscle observed in both animal colitis models and human inflammatory bowel diseases. However, the mechanisms are not well understood. The effects of IL-1beta on the signaling targets mediating acetylcholine (ACh)-induced initial and sustained contraction were examined using rabbit colonic circular muscle strips and cultured muscle cells. The contraction was assessed through cell length decrease, myosin light chain (MLC(20)) phosphorylation, and activation of PLC-beta and Rho kinase. Expression levels of the signaling targets were determined by Western blot analysis and real-time RT-PCR. Short interfering RNAs (siRNAs) for regulator of G protein signaling 4 (RGS4) were used to silence endog

SUBMITTER: Hu W 

PROVIDER: S-EPMC4123227 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature