Vasodilator
From Free net encyclopedia
Vasodilation is where blood vessels in the body become wider following the relaxation of the smooth muscle in the vessel wall. This will reduce blood pressure - since there is more room for the blood. The opposite physiological process is vasoconstriction.
Vasomotor refers to the muscles and nerves controlling the process of vasodilation.
A vasodilator is a substance that causes vasodilation. Several vasodilators are used as drugs which may, for example, allow blood to flow more easily around a clot.
Flushing may be a physiological response to vasodilators.
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Natural vasodilators and Drugs that Exploit Them
- Absence of high levels of environmental noise
- Adenosine
- Adenocard - this is primarily used as an anti-arrhythmic.
- Adrenaline and noradrenaline vasodilate arterioles of the skeletal muscles. (By acting on beta-2 adrenergic receptors.) These chemicals cause vasoconstriction elsewhere.
- Alpha blockers (block the constricting effect of adrenaline).
- Atrial natriuretic peptide (ANP) - a weak vasodilator.
- Bradykinin
- Histamine
- Complement proteins C3a, C4a and C5a work by triggering histamine release from mast cells and basophil granulocytes.
- L-Arginine
- Niacin (aka nicotinic acid)
- Nitric oxide
- Glyceryl trinitrate (commonly known as Nitroglycerin)
- Isosorbide mononitrate & Isosorbide dinitrate
- Pentaerythritol Tetranitrate (PETN)
- Sodium nitroprusside
- PDE5 inhibitors: these agents indirectly increase the effects of nitric oxide
- Platelet activating factor (PAF)
- Prostacyclin (PGI2) as well as other prostaglandins.
- Tetrahydrocannabinol (THC) - the major active chemical in marijuana. Its mild vasodilating effects redden the eyes of cannabis smokers.
- Papaverine an alkaloid found in the opium poppy papaver somniferum