RCSB PDB

139555 Biological Macromolecular Structures Enabling Breakthroughs in Research and Education

NH4

AMMONIUM ION

NH4 is found in 196 entries

NH4 as free ligands, exist in 196 entries. Examples include 1CPD, 1D6O, 1D7H

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View summary at Ligand Expo

Chemical Component Summary
Name	AMMONIUM ION
Identifiers	ammonium azanium
Formula	H₄ N
Molecular Weight	18.04 g/mol
Type	non-polymer
Isomeric SMILES	[NH4+]
InChI	InChI=1S/H3N/h1H3/p+1
InChI Key	QGZKDVFQNNGYKY-UHFFFAOYSA-O

Chemical Details
Formal Charge	1
Atom Count	5
Chiral Atom Count	0
Chiral Atoms
Bond Count	4
Aromatic Bond Count	0

Drug Info: DrugBank

DrugBank ID	DB09326 (Different stereochemistry)
Name	Ammonia N-13
Groups	approved
Description	Ammonia N 13 Injection, USP is a positron emitting radiopharmaceutical that is used for diagnostic purposes in conjunction with positron emission tomography (PET) imaging. The active ingredient, [13N] ammonia, has the molecular formula of 13NH3 with a molecular weight of 16.02. Ammonia N 13 Injection, USP is used for imaging of the myocardium under rest or pharmacologic stress conditions to evaluate myocardial perfusion in patients with suspected or existing coronary artery disease.
Synonyms	(13N)Ammonia Ammonia N 13
Brand Names	Ammonia N 13 Ammonia N 13 N 13 Ammonia N-13 Ammonian 13 N 13
Indication	For diagnostic Positron Emission Tomography (PET) imaging of the myocardium under rest or pharmacologic stress conditions to evaluate myocardial perfusion in patients with suspected or existing coronary artery disease.
Pharmacology	Following intravenous injection, ammonia N 13 enters the myocardium through the coronary arteries. The PET technique measures myocardial blood flow based on the assumption of a three-compartmental disposition of intravenous ammonia N 13 in the myocardium. In this model, the value of the rate constant, which represents the delivery of blood to myocardium, and the fraction of ammonia N 13 extracted into the myocardial cells, is a measure of myocardial blood flow. Optimal PET imaging of the myocardium is generally achieved between 10 to 20 minutes after administration.
Mechanism of action	Ammonia N 13 Injection is a radiolabeled analog of ammonia that is distributed to all organs of the body after intravenous administration. It is extracted from the blood in the coronary capillaries into the myocardial cells where it is metabolized to glutamine N 13 and retained in the cells. The presence of ammonia N 13 and glutamine N 13 in the myocardium allows for PET imaging of the myocardium.
Route of administration	Intravenous
CAS number	34819-78-8

Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS. Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID: 21059682

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