Upregulation of P2X(7) receptor currents in Müller glial cells during proliferative vitreoretinopathy.

摘要: PURPOSE. Muller glial cells from the human retina express purinergic P2X 7 receptors. Because extracellular adenosine triphosphate (ATP) is assumed to be a mediator of induction or maintenance gliosis, this study was undertaken determine whether expression these receptors different in obtained retinas healthy donors and patients with choroidal melanoma proliferative vitreoretinopathy (PVR). METHODS. Human were enzymatically isolated donor retinas, whole-cell patch-clamp recordings made characterize density currents activation through Ca 2+ -activated K + channels big conductance (I BK ) that reflects increase intracellular concentration. RESULTS. Stimulation by external ATP benzoylbenzoyl (BzATP) evoked both release thapsigargin-sensitive stores opening -permeable channels. These responses caused transient sustained increases I . In PVR, mean BzATP-evoked cation significantly greater compared donors. As consequence, such displayed an enlarged during application agonists. BzATP increased DNA synthesis rate cultured cells. This effect could reversed blocking CONCLUSIONS. The receptor may permit higher level entry into PVR. Enhanced subsequent stronger contribute activity gliotic