ammonia

ammonia

 [ah-mo´nyah]

a colorless alkaline gas, NH₃, with a pungent odor and acrid taste, and soluble in water.

ammonia N 13 ammonia in which a portion of the molecules are labeled with ¹³N; used in positron emission tomography of the cardiovascular system, brain, and liver.

am·mo·ni·a

(ă-mō'nē-ă),

A colorless volatile gas, NH₃, highly soluble in water, capable of forming a weak base, which combines with acids to form ammonium compounds.

[fr. L. sal ammoniacus, salt of Amen (G. Ammōn), obtained near a temple of Amen in Libya]

ammonia

/am·mo·nia/ (ah-mōn´yah) a colorless alkaline gas with a pungent odor and acrid taste, NH3. Ammonia labeled with 13N is used in positron emission tomography of the cardiovascular system, brain, and liver.

ammonia (NH3)

[amō′nē·a/]

Etymology: Gk, ammoniakos, salt of Ammon, Egyptian god

a colorless pungent gas produced by the decomposition of nitrogenous organic matter. Some of its many uses are as a fertilizer, an aromatic stimulant, a detergent, and an emulsifier.

ammonia

Biochemistry
An irritating, water-soluble, strongly basic, colourless gas, which is lighter than air.
 
Industry
Ammonia (NH3) is used in explosives, fertilisers, refrigerants and household cleaning solutions.
 
Physiology
NH3 is produced in the liver, intestine and kidneys as an end-product of protein metabolism; the liver converts ammonia into urea, which is then excreted by the kidneys; in liver disease this conversion is decreased, resulting in increased serum ammonia. Serial measurement of ammonia is used to follow progression of hepatic encephalopathy in Reye syndrome and other conditions.
 
Ref range
15–49 µg/dL.
 
Abnormal values
Increased hepatic coma, Reye syndrome, severe CHF, GI haemorrhage, erythroblastosis fetalis, drugs (e.g., diuretics and antibiotics).

ammonia

NH₃ Physiology NH₃ is produced in the liver, intestine, and kidneys as endproduct of protein metabolism; the liver converts ammonia into urea, which is then excreted by the kidneys; in liver disease this conversion is diminished, resulting in ↑ serum ammonia; serial measurement of ammonia is used to follow the progression of hepatic encephalopathy in Reye syndrome and other conditions Ref range 15-49 µg/dL Abnormal values ↑ Hepatic coma, Reye syndrome, severe CHF, GI hemorrhage, erythroblastosis fetalis, drugs–eg, diuretics and antibiotics. See Hepatic encephalopathy.

am·mo·nia

(NH₃) (ă-mō'nē-ă)

A colorless volatile gas, NH₃, highly soluble in water, capable of forming a weak base, which combines with acids to form ammonium compounds.

[fr. L. sal ammoniacus, salt of Amen (G. Ammōn), obtained near a temple of Amen in Libya]

ammonia

A substance produced when AMINO ACIDS are broken down. Ammonia is converted by the liver into urea and excreted in the urine. Urea can be broken down by bacterial enzymes to release ammonia. This may be a cause of nappy rash in babies.

ammonia

a colourless gas, which is the main form in which nitrogen is utilized in living cells. Formula: NH3.

am·mo·nia

(ă-mō'nē-ă)

A colorless volatile gas, NH₃, highly soluble in water, capable of forming a weak base, which combines with acids to form ammonium compounds.

[fr. L. sal ammoniacus, salt of Amen (G. Ammōn), obtained near a temple of Amen in Libya]

ammonia,

n a colorless aromatic gas consisting of nitrogen and hydrogen, produced by the decomposition of nitrogenous organic matter. Some of its many uses are as an aromatic stimulant, a detergent, and an emulsifier.

ammonia thiosulfate

n an ingredient of the photographic fixing solution that acts as a solvent for silver halides.

ammonia

a colorless alkaline gas, NH₃, with a pungent odor and acrid taste, and highly soluble in water. See also ammonium.

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blood ammonia

ammonia is a cerebrointoxicant and a high blood level causes a degenerative brain lesion. High blood levels of ammonia can occur in a number of diseases of the liver, in portacaval shunts, urea poisoning and liver dysfunction.

ammonia clearance

see ammonia tolerance test (below).

ammonia poisoning

ammonia gas may be released from artificial fertilizers or from decomposing manure and urine in slurry pits and silos and cause chronic poisoning manifested by conjunctivitis and coughing, sneezing and dyspnea. May cause dermatitis in animals bedded for long periods on deep litter. Acute poisoning causes heavy mortalities, as in urea poisoning. A secondary effect of chronic poisoning is hepatic encephalopathy. High ammonia content in water can cause deaths of fish, although additional factors such as high levels of suspended organic matter may be contributory.

ammonia pollution

of barn gases by production from fermentation of urine.

ammonia tolerance test (ATT)

assesses liver function and is particularly useful in detecting abnormalities of the hepatic portal vascular system. Blood ammonia levels are measured before and after the oral administration of ammonium chloride. See also portacaval shunt.