What is the purpose of adenosine?

Adenosine appears to subserve a number of diverse roles in normal physiology, which include promoting and/or maintaining sleep, regulating the general state of arousal as well as local neuronal excitability, and coupling cerebral blood flow to energy demand.

What does adenosine do to the heart?

Adenosine is known to regulate myocardial and coronary circulatory functions. Adenosine not only dilates coronary vessels, but attenuates beta-adrenergic receptor-mediated increases in myocardial contractility and depresses both sinoatrial and atrioventricular node activities.

What is the mechanism of action of adenosine?

Mechanism of Action Adenosine further classifies as a miscellaneous antiarrhythmic drug outside the Vaughan-Williams classification scheme. It acts on receptors in the cardiac AV node, significantly slowing conduction time.

How does adenosine cause vasodilation?

In some types of blood vessels, there is evidence that adenosine produces vasodilation through increases in cGMP, which leads to inhibition of calcium entry into the cells as well as opening of potassium channels. In cardiac tissue, adenosine binds to type 1 (A1) receptors, which are coupled to Gi-proteins.

What does adenosine do to the brain?

In the brain adenosine is an inhibitory neurotransmitter. This means, adenosine can act as a central nervous system depressant. In normal conditions, it promotes sleep and suppresses arousal.

What type of drug is adenosine?

Adenosine is a prescription drug used for conversion to sinus rhythm of paroxysmal supraventricular tachycardia (PVST), including that associated with accessory bypass tracts (Wolff-Parkinson-White Syndrome).

Does adenosine drop blood pressure?

Adenosine lowers blood pressure, produces late (probably reflex) tachycardia, and has no effect on ventilation when infused into descending aorta (right panel). Increases in blood pressure and ventilation are, therefore, probably ex- plained by activation of arterial chemoreceptors. (Data obtained from Reference 60.)

What class of drug is adenosine?

Because of the effects of adenosine on AV node-dependent SVTs, adenosine is considered a class V antiarrhythmic agent.

How does adenosine work in the brain?

Adenosine is a central nervous system neuromodulator that has specific receptors. When adenosine binds to its receptors, neural activity slows down, and you feel sleepy. Adenosine thus facilitates sleep and dilates the blood vessels, probably to ensure good oxygenation during sleep.

Is adenosine a vasoconstrictor?

In the renal vasculature, in contrast, adenosine can produce vasoconstriction, a response that has been suggested to be an organ-specific version of metabolic control designed to restrict organ perfusion when transport work increases.

Is dobutamine a vasodilator?

In non-responders, dobutamine mainly acted as a vasodilator, since blood pressure decreased, and cardiac index marginally increased.

Why does adenosine make you sleepy?

Our neurons, or nerve cells, are embedded with adenosine receptors. When adenosine binds to these receptors, a variety of proteins that inhibit neurons are released. This suppression of nerve cell activity is what causes the feeling of drowsiness.