It is specifically a Coronary Vasodilator to be used in Horses and Dogs when they need increased coronary flow to perform heavy loads.
In bodybuilding it is injected at least 1 hour before prejudging and is supposed to really bring out vascularity like nothing you have ever seen. You are also supposed to get lightheaded and hyperventilate.
The rec. dose is 400 mg for a 200 lbs bodybuilder. I just did a trial run with it the other day and got absolutely no effects from it whatsoever, good or bad. Skip and some others swear by it. I know several people who also had similar results as myself. It is possible that it is dose related, so I am going to up my next shot to 500 mg. This starts to get dangeroud, however, because if you take to much you will pass out from lack of oxygen to the brain - Sounds like fun, huh?