Figure 7 - RhoA in LES tone and PGF₂-induced sustained contraction.

a: In LES circular muscle cells, PGF₂ caused a relatively rapid initial contraction that was maintained in excess of 20 minutes. In the presence of the Rho kinase inhibitor Y27632 the initial phase of contraction in response to PGF₂ was not affected. The sustained contraction, however, was almost abolished by Y27632, indicating that the initial and the sustained phase of contraction are mediated through different intracellular pathways. b: The Rho kinase inhibitor Y27632 reduced LES sustained contraction in response to PGF₂, confirming the participation of RhoA in maintenance-sustained contraction in muscle strips as well as in isolated muscle cells. (Source: Harnett et al.,³ with permission from the American Physiological Society.)