Figure 6.
Elastase-induced contractions of pregnant rat myometrial strips. Similar to matrix metalloproteinase-1 (MMP-1), elastase stimulated powerful contractions of the rat myometrium (A). B, Elastase-induced contractions were prevented by inhibition of protease-activated receptor 1 (PAR-1). Elastase-induced contractions were abolished by pretreatment with the inositol trisphosphate receptor (IP3R) blocker (C), as well as calcium channel blockade (data not shown), demonstrating that the downstream signaling mechanism for PAR-1-mediated contraction was IP3-induced release of calcium.