Lubricate throttle spring and axle - with what?

I plan on cleaning the MAF and throttle body today or tomorrow. In reading up on that I have seen suggestions to lubricate the spring and the "axle" where it passes through the body, on each side of the plate. However, nobody said what to use for said lubrication. I will be using throttle body cleaner, which is supposed to leave some lubricant behind, but if that was sufficient, probably there would have been no specific mention of lubricating those points.

So, what, if anything, does one spray on the spring or axle? For the latter I'm most tempted to go with "nothing" since I fear that anything substantial, like grease, will just gunk up the area and eventually cause the plate to stick.

Thanks

 

By "each end", you mean a drop on the axle, where it meets the throttle body, in line with the screws?

This picture was after I cleaned it (but before you posted). I will go back at some point and oil it, it wasn't hard removing the plastic box above the throttle. Well, other than the bar of relays blocking access to the back bolt with a normal sized ratchet. I used strips of old flannel pajamas soaked in CRC Throttle and Air Intake Cleaner. The black sooty stuff came off the aluminum and brass plate easily. There wasn't very much of that above the flap, but it was pretty dark underneath. However, the plate seems to be stained in some way, as I tried and tried and that mottling (which looks a little like rust, but probably cannot be because that plate seems to be brass) just wouldn't come off with that method. It didn't feel rough or raised, so I doubt it is interfering with the function of the throttle.

Any idea what that "stain" might be, and how to clean it? Or maybe best to just ignore it.