Analysis of tissue type plasminogen activator (t-pa) in porcine oviduct”

ROLDÁN OLARTE, M.; VALDECANTOS, P. Y MICELI, D. C.

Tafi del Valle, Tucuman, Argentina

Jornada; XXII Jornadas Científicas de la Asociación de Biología de Tucumán; 2005

Asociación de Biología de Tucumán

ANALYSIS OF TISSUE TYPE PLASMINOGEN ACTIVATOR (t-PA) IN PORCINE OVIDUCT. Mariela Roldán-Olarte, Pablo Valdecantos and Dora C. Miceli. Instituto de Biología. Facultad de Bioquímica, Química y Farmacia. INSIBIO. UNT. Chacabuco 461. 4000. San Miguel de Tucumán. emroldanolarte@fbqf.unt.edu.ar Plasminogen activators are highly specific serine-proteases that convert plasminogen to plasmin, an active protease with a very broad spectrum of substrates. In previous works, we determined the activity of plasminogen activators and the expression of urokinase type plasminogen activator (u-PA) in the epithelium of the porcine oviduct. The aim of this work was to demonstrate that tissue type plasminogen activator (t-PA) is synthesized in the porcine oviduct and to study the differences between follicular and luteal phases of the estrous cycle. Western Blot assays performed with oviductal fluid obtained by flushing oviducts of follicular and luteal phases, with a monoclonal antibody against t-PA, showed a band of 72 kDa indicating the presence of t-PA in both phases of the estrous cycle. The concentration of the protein detected was higher in samples corresponding to follicular phase than luteal phase. The expression of t-PA gene studied by semi-quantitative RT-PCR in both ampulla and isthmus oviductal regions indicated no significant differences between samples. When we studied the t-PA gene in the epithelial cells, it was observed that this tissue specially express that gene especially during the follicular phase. According with these results the presence of t-PA in epithelial cells was confirmed by immunohistochemical assays. These results indicate that the t-PA is synthesized in the porcine oviduct. This enzyme could be secreted to the oviductal lumen, where it could activate plasminogen to plasmin near gametes or embryos. This enzyme could act directly over extracellular matrix components or indirectly, probably by activating matrix metalloproteases or grow factors.