Urokinase-type plasminogen activator (uPA) promotes the axonal outgrowth in retinal ganglion cells.

MEDORI, MARA; FIORE, LUCIANO; SPELZINI, GONZALO; RAPACIOLI MELINA; SCICOLONE, GABRIEL; SANCHEZ, VIVIANA

Mar del Plata

Congreso; XXX SAN Annual Meeting; 2015

Sociedad Argentina de Investigación en Neurociencias

Urokinase-type plasminogen activator (uPA) promotes the axonal outgrowth in retinal ganglion cellsMedori M.1; Fiore L. 1, Spelzini G. 1;Rapacioli M.2; Scicolone G. 1; Sanchez V1. (IBCN1; Univ. Favaloro2)Urokinase type plasminogen activator (uPA) is a serine protease which facilitates growth cone movement by local proteolysis of extracellular matrix. Recently we have demonstrated that the interaction between uPA and its receptor (uPAR) induces the neuronal migration and neuritogenesis by both proteolytic activity and nonproteolytic events throughout the activation of intracellular signaling in migrating neurons of the developing chicken Optic Tectum.In this work we investigated whether the uPA:uPAR complex participates in the axonal growth of retinal ganglion cells (RGC). We performed cultures of retinal explants from chicken embryos of 7 days. Some explants were treated with 10 nM of uPA. By immunocytochemistry we indentified the presence of uPAR in the axonal growth cones of RGC. On the other hand we performed time-lapse experiments with control and experimental explants. The cultures were photographed during 3 hours and we measured the length of the axons each 30 minutes in both control and uPA stimulated explants.The results showed that after 3 hours, the axons exposed to uPA stimulation grew 118% (p<0.05) more than the control axons. The growth rate was also higher in uPA-stimulated axons in relationship with control ones (78,04 m/h vs 44,24 m/h respectively, p<0.05). In summary we could determine that uPA:uPAR system promotes the axonal growth of RGC during the development of the retina. This work was supported by grants of CONICET and UBACyT.