A vasoactive substance is an
endogenous
Endogeny, in biology, refers to the property of originating or developing from within an organism, tissue, or cell.
For example, ''endogenous substances'', and ''endogenous processes'' are those that originate within a living system (e.g. an ...
agent or
pharmaceutical drug
Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the ...
that has the effect of either increasing or decreasing
blood pressure
Blood pressure (BP) is the pressure of Circulatory system, circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term ...
and/or
heart rate
Heart rate is the frequency of the cardiac cycle, heartbeat measured by the number of contractions of the heart per minute (''beats per minute'', or bpm). The heart rate varies according to the body's Human body, physical needs, including the nee ...
through its vasoactivity, that is, vascular activity (effect on
blood vessel
Blood vessels are the tubular structures of a circulatory system that transport blood throughout many Animal, animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the Tissue (biology), tissues of a Body (bi ...
s). By adjusting
vascular compliance and
vascular resistance
Vascular resistance is the resistance that must be overcome for blood to flow through the circulatory system. The resistance offered by the systemic circulation is known as the systemic vascular resistance or may sometimes be called by another ter ...
, typically through
vasodilation
Vasodilation, also known as vasorelaxation, is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. Blood vessel wa ...
and
vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vesse ...
, it helps the body's
homeostatic mechanisms (such as the
renin–angiotensin system
The renin–angiotensin system (RAS), or renin–angiotensin–aldosterone system (RAAS), is a hormone system that regulates blood pressure, fluid, and electrolyte balance, and systemic vascular resistance.
When renal blood flow is reduced, ...
) to keep
hemodynamics
Hemodynamics or haemodynamics are the dynamics of blood flow. The circulatory system is controlled by homeostatic mechanisms of autoregulation, just as hydraulic circuits are controlled by control systems. The hemodynamic response continuously ...
under control. For example,
angiotensin
Angiotensin is a peptide hormone that causes vasoconstriction and an increase in blood pressure. It is part of the renin–angiotensin system, which regulates blood pressure. Angiotensin also stimulates the release of aldosterone from the adr ...
,
bradykinin
Bradykinin (BK) (from Greek ''brady-'' 'slow' + ''-kinin'', ''kīn(eîn)'' 'to move') is a peptide that promotes inflammation. It causes arterioles to dilate (enlarge) via the release of prostacyclin, nitric oxide, and endothelium-derived hyperpo ...
,
histamine
Histamine is an organic nitrogenous compound involved in local immune responses communication, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Discovered in 19 ...
,
nitric oxide
Nitric oxide (nitrogen oxide, nitrogen monooxide, or nitrogen monoxide) is a colorless gas with the formula . It is one of the principal oxides of nitrogen. Nitric oxide is a free radical: it has an unpaired electron, which is sometimes den ...
, and
vasoactive intestinal peptide
Vasoactive intestinal peptide, also known as vasoactive intestinal polypeptide or VIP, is a peptide hormone that is vasoactive in the intestine. VIP is a peptide of 28 amino acid residue (chemistry), residues that belongs to a Secretin family, glu ...
are important endogenous vasoactive substances. Vasoactive drug therapy is typically used when a patient has the blood pressure and heart rate
monitored constantly. The
dosage is typically titrated (adjusted up or down) to achieve a desired effect or
range of values as determined by competent clinicians.
Vasoactive drugs are typically administered using a volumetric infusion device (IV pump). This category of
drug
A drug is any chemical substance other than a nutrient or an essential dietary ingredient, which, when administered to a living organism, produces a biological effect. Consumption of drugs can be via insufflation (medicine), inhalation, drug i ...
s require close observation of the patient with near immediate intervention required by the
clinician
A clinician is a health care professional typically employed at a skilled nursing facility or clinic. Clinicians work directly with patients rather than in a laboratory, community health setting or in research. A clinician may diagnose, treat a ...
s in charge of the patient's care. Important vasoactive substances are
angiotensin
Angiotensin is a peptide hormone that causes vasoconstriction and an increase in blood pressure. It is part of the renin–angiotensin system, which regulates blood pressure. Angiotensin also stimulates the release of aldosterone from the adr ...
-11,
endothelin-1, and alpha-
adrenergic agonists.
Various vasoactive agents, such as
prostanoids,
phosphodiesterase inhibitors, and endothelin antagonists, are approved for the treatment of
pulmonary arterial hypertension
Pulmonary arterial hypertension (PAH) is a syndrome in which the blood pressure in the pulmonary arteries and pulmonary arterioles (the blood vessels located proximal to the capillary bed, the site of oxygen exchange in the lungs) is elevated. T ...
. The use of vasoactive agents for patients with pulmonary hypertension may cause harm and unnecessary expense to persons with
left heart disease or
hypoxemic types of
lung disease
The lungs are the primary organs of the respiratory system in many animals, including humans. In mammals and most other tetrapods, two lungs are located near the backbone on either side of the heart. Their function in the respiratory syst ...
s.
References
Drugs
{{Drug-stub