Etilefrine is a

cardiac stimulant A cardiac stimulant is a substance which acts as a stimulant of the heart – e.g., via positive chronotropic or inotropic An inotrope is an agent that alters the force or energy of muscular contractions. Negatively inotropic agents weaken the fo ...

used as an

antihypotensive An antihypotensive agent, also known as a vasopressor agent or simply vasopressor, or pressor, is any substance, whether endogeny (biology), endogenous or a medication, that tends to raise low blood pressure. Some antihypotensive drugs act as vas ...

. It is a

sympathomimetic amine Sympathomimetic drugs (also known as adrenergic drugs and adrenergic amines) are stimulant compounds which mimic the effects of endogenous agonists of the sympathetic nervous system. Examples of sympathomimetic effects include increases in heart ...

of the 3-hydroxy-phenylethanolamine series used in treating

orthostatic hypotension Orthostatic hypotension, also known as postural hypotension, is a medical condition wherein a person's blood pressure drops when standing up or sitting down. Primary orthostatic hypertension is also often referred to as neurogenic orthostatic hyp ...

of neurological, cardiovascular, endocrine or metabolic origin.

Intravenous infusion Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...

of this compound increases cardiac output, stroke volume,

venous return Venous return is the rate of blood flow back to the heart. It normally limits cardiac output. Superposition of the cardiac function curve and venous return curve is used in one hemodynamic model. __TOC__ Physiology Venous return (VR) is the flow o ...

and blood pressure in man and experimental animals, suggesting stimulation of both α and β adrenergic receptors. However, ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called " test-tube experiments", these studies in biology ...

'' studies indicate that etilefrine has a much higher affinity for β₁ (cardiac) than for β₂

adrenoreceptors The adrenergic receptors or adrenoceptors are a class of G protein-coupled receptors that are targets of many catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) produced by the body, but also many medications like beta ...

. Intravenous etilefrine increases the pulse rate, cardiac output, stroke volume,

central venous pressure Central venous pressure (CVP) is the blood pressure in the venae cavae, near the right atrium of the heart. CVP reflects the amount of blood returning to the heart and the ability of the heart to pump the blood back into the arterial system. CVP ...

and

mean arterial pressure In medicine, the mean arterial pressure (MAP) is an average blood pressure in an individual during a single cardiac cycle. MAP is altered by cardiac output and systemic vascular resistance. Testing Mean arterial pressure can be measured dire ...

of healthy individuals. Peripheral vascular resistance falls during the infusion of 1–8 mg etilefrine but begins to rise at higher dosage. Marked falls in pulse rate, cardiac output, stroke volume and peripheral bloodflow, accompanied by rises in mean arterial pressure, occur when etilefrine is infused after administration of intravenous

propranolol Propranolol, sold under the brand name Inderal among others, is a medication of the beta blocker class. It is used to treat high blood pressure, a number of types of irregular heart rate, thyrotoxicosis, capillary hemangiomas, performance an ...

2,5 mg. These findings indicate that etilefrine has both β₁ and α₁ adrenergic effects in man.

References

External links

* * {{Phenethylamines Alpha-1 adrenergic receptor agonists Alpha-2 adrenergic receptor agonists Beta-adrenergic agonists Cardiac stimulants Phenylethanolamines Phenols