ROLDAN OLARTE Eugenia Mariela
congresos y reuniones científicas
Urokinase type plasminogen activator in porcine oviduct: synthesis and gene expression
Tafi del Valle, Tucuman, Argentina
Jornada; XIX Jornadas Científicas de la Asociación de Biología de Tucumán; 2002
Institución organizadora:
Asociación de Biología de Tucumán
86. UROKINASE TYPE PLASMINOGEN ACTIVATOR IN PORCINE OVIDUCT: SYNTHESIS AND GENE EXPRESSION Roldán M, Argañaraz M, Valdecantos P and Miceli D. Fac. Bioquímica, Química y Farmacia.INSIBIO. UNT: Chacabuco 461. 4000. Tucumán. E-mail: Plasminogen activators (PAs) are serine proteases that transform plasminogen in plasmin, which can acts on various substrates, modifying the extracellular matrix. This system has been recently involved in several steps of the reproduction process. Previously we have analyzed PA activity in tissue extract of porcine oviducts and have characterized those activities as tPA (tissue type plasminogen activator) and uPA (urokinase type plasminogen activator). During the sexual cycle, there were differences between follicular and luteal phases indicating their hormonal regulation. The aim of this work was to determine by Westem blot the presence of uPA activity in oviductal flushing. We found only a band of approximately 54 KDa corresponding to uPA. uPA varies during the estrous cycle, it being more intense in metestrus or early luteal phase than previous ovulation stages. To confirm whether uPA increases was due to oviducal synthesis or it is the product of serum transudation or follicular fluid contamination, we verified uPA gene expression by Northem Blot. A hybridization signal at 2,4 Kb corresponding to uPA mRNA was found. The expression levels normalized with b-actin mRNA confirmed that uPA gene transcription is the biggest after ovulation, indicating that uPA is synthesized and secreted differentially in the oviduct during the sexual cycle. The data obtained in this study suggest that this enzyme could act in the remodeling of the eggs extracellular matrix during their transit through the oviduct or in the maintenance of oviductal lumen fluidity.