Vasodilatation

On the natural mechanisms, the vasodilation is generally regarded as an integral process thermoregulation, ie, regulation of body temperature by homeostatic mechanisms, of equilibrium. When there is an increase of the outdoor temperature, there is an increasing body temperature. To counteract this variation, the hypothalamic-pituitary complex (which receives the external message) sends a message that enables nerve vasodilation, and subsequent heat loss to the outside.

Artificial mechanisms a vasodilator is a substance that causes vasodilation. These substances can be used in medicine so as to allow blood flow around a blood clot.
Some of the key substances vasodilatoras:
Adenosine;
Adenocard - antiarrhythmic medication;
Adrenaline and noradrenaline;
Alpha blockers (block the vasoconstrictor effect of adrenaline);
Bradykinin;
Histamine;
L-Arginine;
Niacin (or nicotinic acid);
Nitric oxide.


A positive point in building muscle is more defined and beautiful that has a good blood supply, it is necessary to lower the level of fat in the body. Many athletes who practice bodybuilding seeking this benefit varies greatly from person to person, some are born with this predisposition, others have to chase. 
Few know that the vasculature is not only the increase of the veins, but the new growth through these ancient, ie, that an increase in muscle called "pump" due to the fact that several veins are stagnant and changed. The emergence of new blood vessels occurs through lack of oxygen in the muscle, thus generates a stimulus that generates new molecular veins in order to help bring these oxygens to underserved areas. What is the purpose of someone wanting large veins? Many people think they are aesthetically nicer, but this advantage is not only that there is critical to the increase in lean body mass. The more vascularity you have the more oxygen the body takes to the muscles, and thus achieve a better growth and higher those nutrients to greater muscle hypertrophy.The esthetic level, try lowering your body fat percentage to about 12%, the less fat you have more veins were notorious, if possible do sauna 2 times a week, takes the sweat out excess water and sodium from the skin and muscle and veins become more noticeable and to finalize do not drink too much salt, it retains water and reduces vascularization. 
At the functional use in some (nitric oxide) to increase the capacity of vasodilation and increase blood flow in the vessels, do high repetitions, about 20, it stimulates vascularization, and do cardio to finish, and do well to heart, burns fat and helps dry the body