It still sounds like you're looking for .mousedown()
http://api.jquery.com/mousedown/
To clarify: If you want some code to execute repeatedly until the mouse is released (I can't quite tell if that's actually what you want), you could use something like this:
var interval = -1;
function doThing(){
console.log("this will execute 10 times per second while the mouse is held down");
}
$('#element').mousedown(function(){
if(interval !== -1)
clearInterval(interval);
interval = setInterval(doThing, 100);
});
$('#element').mouseup(function(){
if(interval !== -1)
clearInterval(interval);
});