The involvement of activated ERK signaling pathway in the pathogenesis of endometriosis and ameliorative effect of letrozol

Objective To investigate the involvement of activated extracellular signal- regulated kinase( ERK) signaling transduction pathway in the pathogenesis of endometriosis( EMs) and the ameliorative effect of letrozol. Methods A total of 40 female SD rats were randomly divided into 4 groups: sham group,EMs group,PD98059 group and letrozol group,with 10 rates in each group. The EMs models were duplicated by autoplastic transplantation,PD98059 and letrozol group were gavaged with corresponding drugs. The expression of ERK pathway related proteins Methyl Ethyl Ketone( MEK),extracellular signal- regulated kinase( ERK1 /2),extracellular regulated protein kinase( p MEK),p ERK1 /2 and matrix metalloproteinase( MMP2) as well as Caspase3 were detected by Western Blotting. Results The research showed that the expression of MEK,p MEK,ERK1 /2,p ERK1 /2 were up-regulated greatly( 123. 6 %,136. 4 %,144. 7 %,141. 2 %,134. 7 % and 187. 6 % respectively),the expression of MMP2 and Caspase3 were inceased( 187. 6 % 、134. 7 % respectively). While those abnormal protein expressions of letrozol group normalized significantly,which were lower than those of EMs group( P 0. 05). Conclusion Over- activated ERK signaling pathway and extracellular matrix recombination combined apoptosis are involved in the pathogenesis of EMs and ameliorative effect of letrozol mainly through normalizing the aforementioned parameters.