Las proteínas del plasma seminal incrementan la viabilidad espermática post-descongelación del semen de toros Sanmartinero

Objetivo. El objetivo de este trabajo fue evaluar el efecto de la adicion de proteinas del plasma seminal sobre el porcentaje de espermatozoides bovinos viables post-descongelacion. Materiales y metodos. Los espermatozoides se congelaron usando dos medios (citrato-fructosa-yema y Bioxcell®) y la obtencion de proteinas de plasma seminal de bajo peso molecular se realizo por medio de cromatografia liquida de baja presion. Las proteinas de interes eluyeron en las fracciones 21-25 y se sometieron a electroforesis en una y dos dimensiones. Los espermatozoides se incubaron a 37°C durante una hora, con 0.5, 1.0, 1.5 y 2.0 mg de la fraccion 21-25. Se incluyeron dos tratamientos adicionales: uno con proteinas totales del plasma seminal y otro sin proteina. Resultados. La electroforesis bidimensional de las fracciones confirmo la presencia de siete puntos de proteina de bajo peso molecular (14-16 kDa y punto Isoelectrico de 5.0 - 5.5). La adicion de estas proteinas aumento 20% (p Objective.This study was performed to evaluate the effect of the addition of proteins on the post-thawing viability of spermatozoa. Materials and methods. Spermatozoa were frozen with two different media: Citrate-fructose and Bioxcell®. The isolation of seminal plasma proteins of low molecular weight was performed through low pressure liquid chromatography. It was determined that the proteins of interest eluted in fractions 21-25, and two dimensional electrophoresis was performed. Thawed sperm was incubated at 37°C for one hour with 0.5, 1, 1.5 and 2.0 mg of 21-25 fraction protein. Two additional treatments were included: one with seminal plasma total protein, and another one without protein. Results. Two dimensional electrophoresis of protein confirmed the presence of two bands of 14 and 16 kDa and seven spots with iso-electric points between 5.0 - 5.5 respectively. Incubation of the spermatozoa with the 21-25 fraction showed that sperm viability increases by 20% with doses of 1 and 1.5 mg of protein/106 spermatozoa in the citrate-fructose medium, and 25% with 0.5 mg of protein/106 spermatozoa in Bioxcell® medium. A positive effect in sperm viability was demonstrated although it depends on the doses of protein and the cryopreservation medium used. Conclusions. This investigation suggests that the use of seminal plasma proteins can be useful for reducing the harmful effect on sperm cryopreservation.(AU)