acid phosphatase

acid

 [as´id]

1. sour.

2. a substance that yields hydrogen ions in solution and from which hydrogen may be displaced by a metal to form a salt. For the various acids, see under the specific name, such as acetic acid. All acids react with bases to form salts and water (neutralization). Other properties of acids include a sour taste and the ability to cause certain dyes to undergo a color change. A common example of this is the ability of acids to change litmus paper from blue to red.

Inorganic acids are distinguished as binary or hydracids, and ternary or oxyacids; the former contain no oxygen; in the latter, the hydrogen is united to an electronegative element by oxygen. The hydracids are distinguished by the prefix hydro-. The names of acids end in -ic, except in the case in which there are two degrees of oxygenation. The acid containing the greater amount of oxygen has the termination -ic, the one having the lesser amount has the termination -ous. Acids with the termination -ic form the salts ending in -ate; those ending in -ous form the salts ending in -ite. The salts of hydracids end in -ide. These rules are demonstrated by the acids and salts: hydrochloric acid (HCl), sodium chloride (NaCl), sulfuric acid (H₂SO₄), sodium sulfate (Na₂SO₄), sulfurous acid (H₂SO₃), sodium sulfite (Na₂SO₃). Acids are called monobasic, dibasic, tribasic, and tetrabasic, respectively, when they contain one, two, three, or four replaceable hydrogen atoms.

The most common organic acids are carboxylic acids, containing the carboxyl group (-COOH); examples are acetic acid, citric acid, amino acids, and fatty acids. Their salts and esters end in -ate, e.g., ethyl acetate. Other organic acids are phenols and sulfonic acids.

Acids play a vital role in the chemical processes that are a normal part of the functions of the cells and tissues of the body. A stable balance between acids and bases in the body is essential to life. See also acid-base balance.

acid elution test air-dried blood smears are fixed in 80 per cent methanol and immersed in a pH 3.3 buffer; all hemoglobins are eluted except fetal hemoglobin (HbF), which is seen in red blood cells after staining.

inorganic acid an acid containing no carbon atoms.

acid perfusion test Bernstein test.

acid phosphatase a lysosomal enzyme that hydrolyzes phosphate esters liberating inorganic phosphate and has an optimal pH of about 5.0. Serum activity of the prostatic isoenzyme is greatly increased in metastatic cancer of the prostate and is used to monitor the course of the disease.

---

phosphatase

 [fos´fah-tās]

any of a group of enzymes capable of catalyzing the hydrolysis of esterified phosphoric acid, with liberation of inorganic phosphate, found in practically all tissues, body fluids, and cells, including erythrocytes and leukocytes.

acid phosphatase see acid phosphatase.

alkaline phosphatase see alkaline phosphatase.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

ac·id phos·pha·tase

a phosphatase with an optimum pH of less than 7 (for several isozymes, it is 5.4), notably present in the prostate gland; demonstrable in lysosomes with Gomori nonspecific acid phosphatase stain; it hydrolyzes many orthophosphoric monoesters.

Farlex Partner Medical Dictionary © Farlex 2012

acid phosphatase

A group of enzymes (EC 3.1.3.2) with broad specificity which transphosphorylate.

Haemolysis causes false increase; AP decreased precipitously if improperly preserved. Serum AP was once used to diagnose and monitor the progress of prostate cancer; however, given its non-specificity, AP has been replaced by newer tests—e.g., serum PSA, and immunoassay of prostatic AP.
 
Patient prep
Prostate massage, catheterisation, or rectal examination should be avoided 48 hours before obtaining specimen.
 
Specimen
Frozen serum.

Normally present
Prostate, semen, liver, spleen, RBCs, bone marrow, platelets.
 
Increased in
Prostate cancer or infarction, Paget’s disease, Gaucher’s disease, multiple myeloma.

Ref range
0–1.1 Bodansky U.

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

acid phosphatase

A group of enzymes with broad specificity which transphosphorylates; APs are present in the prostate gland, semen, liver, spleen, RBCs, BM, platelets Ref range 0-1.1 Bodansky U ↑ Prostate CA or infarction, Paget's disease, Gaucher's disease, multiple myeloma. See PSA.

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

ac·id phos·pha·tase

(as'id fos'fă-tās)

A phosphatase with an optimal pH of less than 7.0, notably present in the prostate gland.

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

ac·id phos·pha·tase

(as'id fos'fă-tās)

A phosphatase with an optimal pH of less than 7.0, notably present in the prostate gland.

Medical Dictionary for the Dental Professions © Farlex 2012