[Cyclosporin a induces titin expression in human trophoblast cells through the MEK/ERK1/2 signal pathway]. 
To investigate the role of MEK/ERK1/2 signal pathway in the regulation of cyclosporin A(CsA) -induced titin expression in human trophoblast cells.  With RT-PCR and Western Blot, We examined the titin expression level of human trophoblast cells treated with different concentrations of CsA for various duration, then detected total ERK1/2 and phosphorated ERK1/2 level with Western Blot, and observed effect of U0126 on transcription of titin mRNA in human trophoblast cells stimulated by cyclosporin A. It was found that CsA could activate ERK1/2 in time-dependent and dosage-dependent manner, and induced titin to be expressed in human trophoblast cells.  U0126, a MEK inhibitor, inhibited the transcription of titin in dosage-dependent manner.  These results indicated that MEK/ERK1/2 signal pathway may play an important role in the expression of titin in human trophoblast induced by cyclosporin A.