Modulation of cell matrix adhesion plasticity by bradykinin (BK): a quantitative morphometric study in rat renal papilla collecting duct cells

MÁRQUEZ M. GABRIELA1, FERNÁNDEZ-TOME M. CARMEN, AND STERIN-SPEZIALE NORMA

Rosario, Santa Fe, Argentina

Congreso; XLII Reunión de la Sociedad Argentina de Investigaciones Bioquímicas y Biología Molecular (SAIB); 2006

Sociedad Argentina de Investigaciones Bioquímicas y Biología Molecular (SAIB)

Focal adhesions (FA) are structures of cell attachment to extracelular matrix. We previously found that BK induces a restructuration of FA by mobilizating FA protein vinculin (V), but not talin (T), by a mechanism that involves phosphatidylinositol 4,5 biphosphate hydrolysis by PLC. Now, we performed a detailed quantitative morphometric analysis of FA, which include size, axial ratio (AR) and average length (AL). After 1’, 5’ or 10’ (minutes) BK incubation, cultured cells were immunostained and analyzed by confocal microscopy. BK induced a decrease in the number of V-stained FA per cell (Control vs 1’,5’,10’: 72.0±14.4 vs 25.2±9.8, 29.4±9.1, 30.6±5.1; p<0.05), but not T-stained FA (41.6±4.2 vs 41.2±9.5, 50.6±10.7, 43.5±6.1, pNS). Although V- and T-stained FA shape remained round to ellipsoid in all groups (AR<3), BK induced a great variation in V-stained FA size (mm2) between cells (Control: 0.3-7, 1’: 0.3-25, 5’: 0.3-12, 10’: 0.3-9), but not in T-stained FA. Also induced a great variation in V-and T-stained FA AL. BK induced the formation of “transversal stress fibers” and migratory structures. These results report a roll of BK in modulating the plasticity of V-containing cell matrix adhesions by inducing changes in the morphological characteristics of V-containing FA and actin cytoskeleton, not described yet.