Date of Graduation
Master of Science in Cell and Molecular Biology
microvascular endothelial cells, permeability, focal adhesion kinase, P2YΓéé receptor
Medical Molecular Biology
Microvascular endothelial cells (MEC) lining the vasculature critically control barrier function. Extracellular nucleotides, ATP, have been recognized as inflammatory mediators involved in vascular inflammation acting on G-protein coupled P2Y receptors. In vivo study using wild type and P2Y2 receptor (P2Y2R) knockout mice demonstrates that activation of the P2Y2 receptor induces a transient increase in post-capillary venular permeability to albumin (Ps). The molecular mechanisms regulating permeability by P2Y2R are unknown. It has been demonstrated that activation of P2Y2R promotes integrin-coupled focal adhesion protein complexes signaling cascade. Because focal adhesion kinase (FAK), a key molecule of focal adhesion protein complexes, critically maintains vascular barrier integrity, I hypothesized that FAK would mediate P2Y2R-induced hyperpermeability. To test this hypothesis, primary cultured mouse MEC derived from origin-matched microvessels used for in vivo permeability study were established and employed in this study. UTP (10-5 M and 10-4 M) induced a transient increase in MEC monolayer Ps with a peak after 10 min treatment. UTP (10-5 M) elicited a significant increase in FAK activity at 10 min and 30 min in WT MEC as assessed by immunoblotting. No increase in FAK was found in P2Y2R KO MEC. Inhibition of FAK did not affect basal MEC monolayer Ps. Study of the UTP-induced MEC Ps response in the presence of FAK inhibitor was inconclusive. The findings support the hypothesis that FAK activation is associated with UTP-induced microvascular hyperpermeability response.
© Joseph David Harvey
Harvey, Joseph David, "Modulation of Microvascular Barrier Property By the P2Y2 Receptor: the Role of Focal Adhesion Kinase" (2014). MSU Graduate Theses. 1862.