Adenosine

Adenosine
Clinical data


Trade names	Adenocard; Adenocor; Adenic; Adenoco; Adeno-Jec; Adenoscan; Adenosin; Adrekar; Krenosin
AHFS/Drugs.com	Monograph
Pregnancy category	B (adenosine may appear to be safe to the fetus in pregnant women)
Routes of administration	Intravenous
ATC code	C01EB10 (WHO)
Legal status
Legal status	℞ (Prescription only)
Pharmacokinetic data
Bioavailability	Rapidly cleared from circulation via cellular uptake
Protein binding	No
Metabolism	Rapidly converted to inosine and adenosine monophosphate
Biological half-life	cleared plasma <30 seconds – half-life <10 seconds
Excretion	can leave cell intact or can be degraded to hypoxanthine, xanthine, and ultimately uric acid
Identifiers
IUPAC name (2R,3R,4S,5R)-2-(6-amino-9H-purin-9-yl)-5-(hydroxymethyl)oxolane-3,4-diol
Synonyms	SR-96225 (developmental code name)
CAS Number	58-61-7^Y
PubChem (CID)	60961
IUPHAR/BPS	2844
DrugBank	DB00640^Y
ChemSpider	54923^Y
UNII	K72T3FS567^Y
KEGG	C00212^Y
ChEBI	CHEBI:16335^Y
ChEMBL	CHEMBL477^N
ECHA InfoCard	100.000.354
Chemical and physical data
Formula	C₁₀H₁₃N₅O₄
Molar mass	267.241 g/mol
3D model (Jmol)	Interactive image
SMILES n2c1c(ncnc1n(c2)[C@@H]3O[C@@H]([C@@H](O)[C@H]3O)CO)N
InChI InChI=1S/C10H13N5O4/c11-8-5-9(13-2-12-8)15(3-14-5)10-7(18)6(17)4(1-16)19-10/h2-4,6-7,10,16-18H,1H2,(H2,11,12,13)/t4-,6-,7-,10-/m1/s1^Y Key:OIRDTQYFTABQOQ-KQYNXXCUSA-N^Y
^NY (what is this?)

(adenosine may appear to be safe to the fetus in pregnant women)

Adenosine is a purine nucleoside composed of a molecule of adenine attached to a ribose sugar molecule (ribofuranose) moiety via a β-N₉-glycosidic bond. Adenosine is widely found in nature and plays an important role in biochemical processes, such as energy transfer—as adenosine triphosphate (ATP) and adenosine diphosphate (ADP)—as well as in signal transduction as cyclic adenosine monophosphate (cAMP). It is also a neuromodulator, believed to play a role in promoting sleep and suppressing arousal. Adenosine also plays a role in regulation of blood flow to various organs through vasodilation.

In addition to adenosine's endogenous forms, it is also used as a medication, specifically, as an antiarrhythmic agent, to treat a number of forms of supraventricular tachycardia that do not improve with vagal maneuvers. Common side effects include chest pain, feeling faint, shortness of breath along with tingling of the senses . Serious side effects include a worsening dysrhythmia and low blood pressure. It appears to be safe in pregnancy.

When it is administered intravenously, adenosine causes transient heart block in the atrioventricular (AV) node. This is mediated via the A₁ receptor, inhibiting adenylyl cyclase, reducing cAMP and so causing cell hyperpolarization by increasing inward K+ flux via inward rectifier K+ channels, subsequently inhibiting Ca²⁺ current. It also causes endothelial-dependent relaxation of smooth muscle as is found inside the artery walls. This causes dilation of the "normal" segments of arteries, i.e. where the endothelium is not separated from the tunica media by atherosclerotic plaque. This feature allows physicians to use adenosine to test for blockages in the coronary arteries, by exaggerating the difference between the normal and abnormal segments.

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Wikipedia