var imgOcultar = new Image();
imgOcultar.src = '../Images/Default/Buttons/BEOcultar.png';

var imgMostrar = new Image();
imgMostrar.src = '../Images/Default/Buttons/BEMostrar.png';

function Pulsar(obj) {
    var contenedor = obj.parentNode.parentNode.parentNode.parentNode.parentNode;
    if (obj.nameProp == 'BEMostrar.png') {
        contenedor.childNodes[1].style.display = 'inline'
        obj.src = imgOcultar.src;
    }
    else {
        contenedor.childNodes[1].style.display = 'none';
        obj.src = imgMostrar.src;
    }
    
}