alkaline phosphatase (redirected from Alkaline phosphotase)

alkaline phosphatase /al·ka·line phos·pha·tase/ (ALP) (fos´fah-tās) an enzyme that catalyzes the cleavage of orthophosphate from orthophosphoric monoesters under alkaline conditions. Differing forms of the enzyme occur in normal and malignant tissues. The activity in serum is useful in the clinical diagnosis of many illnesses. Deficient bone enzyme activity, an autosomal recessive trait, causes hypophosphatasia.

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leukocyte alkaline phosphatase  (LAP) the isozyme of alkaline phosphatase occurring in the leukocytes, specifically in the neutrophils; LAP activity is used in the differential diagnosis of neutrophilia, being lowered in chronic myelogenous leukemia but elevated in a variety of other disorders.

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alkaline phosphatase

n.

A phosphatase with an optimum functioning at pH 8.6; it is present throughout the body.

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Alkaline phosphatase

An enzyme found throughout the body, primarily in liver, bone, placenta, and intestine.

Mentioned in: Alkaline Phosphatase Test

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alkaline phosphatase,

an enzyme present in all tissues and in high concentration in bone, kidneys, intestines, biliary ducts, plasma, and teeth. It may be elevated in serum in some diseases of the bone and liver and some other illnesses. Normal serum concentrations in adults are 1.5 to 4.5 Bodansky units; in children, 5 to 14 Bodansky units. See also acid phosphatase.

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alkaline (al´klin),

adj having the reductions of an alkali. A pH level of 7.1 to 14 designates an alkaline solution. See also basic.

alkaline diet,

n See diet, alkaline.

alkaline phosphatase,

n an enzyme present in bone, the kidneys, the intestines, plasma, and teeth. It may be elevated in the serum in some diseases associated with disturbances in bone, liver, or other tissues.

alkaline reserve,

n See reserve, alkaline.

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phosphatase(s) (fos´ftās),

n a group of enzymes that are distributed throughout most cells and body fluids and are characterized by their ability to hydrolyze a wide variety of monophosphate esters to alcohols and inorganic phosphate.

phosphatase, acid,

n a group of phosphatases (e.g., serum, liver, prostate) with optimal activity below a pH level of 7. Elevated serum levels have been observed in metastatic breast and prostatic cancer; Paget's, Gaucher's, and Niemann-Pick diseases and in myelocytic leukemia.

phosphatase, alkaline,

n a group of phosphatases (e.g., serum, liver, bone) whose optimal activity ranges near a pH level of 9.8. Elevated blood levels occur in Paget's disease and pregnancy, whereas low levels are characteristic of dwarfism and a generalized nutritional protein deficiency.

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alkaline

having the reactions of an alkali.

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alkaline incompatibilities

a basic chemical fact that acids and alkalis react together so that the mixing of them in medications is likely to render the medicine ineffective. The phenomenon is utilized in the treatment of poisoning when the objective is to combat the effects of an ingested substance.

alkaline phosphatase

a nonspecific enzyme localized on cell membranes that hydrolyzes phosphate esters liberating inorganic phosphate and has an optimal pH of about 9.5. Serum alkaline phosphatase activity is elevated in hepatobiliary disease, especially in obstructive jaundice, and in bone diseases with increased osteoblastic activity such as hyperparathyroidism, osteitis deformans and bone cancer. The liver and bone tissue each produce a distinct isoenzyme. Called also AP, alkaline phosphomonoesterase, glycerophosphatase.

alkaline picrate test

a technique for estimating urine creatinine levels.

alkaline tide

see postprandial alkaline tide.

alkaline urine

the urine of carnivores is acidic, that of herbivores is alkaline. The presence of an alkaline urine in a carnivore, provided the sample is fresh and uncontaminated, is an indication that the patient is alkalotic, but urine findings must always be interpreted with caution.

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phosphatase

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.

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acid phosphatase

a lysosomal enzyme that hydrolyzes phosphate esters liberating phosphate, showing optimal activity at a pH between 3 and 6; found in erythrocytes, prostatic tissue, spleen, kidney and other tissues.

alkaline phosphatase

an isoenzyme showing optimal activity at a pH of about 10; found in bone, liver, kidney, leukocytes, adrenal cortex and other tissues, often used in clinical diagnosis of liver and/or bone damage. Called also AP; see also alkaline phosphatase.

phosphatase inhibitor-1

inhibitor of phosphatase enzymes known to activate glycogen synthesis or inactivate glycogen breakdown. Need to themselves be phosphorylated by cAMP-dependent kinases before they are effective in their inhibitory activity.

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alkaline phosphatase

'Alk phos' Clinical chemistry A 69 kD homodimeric metalloenzyme with broad specificity, which is widely distributed in nature, has an optimal activity at a high–± 10 pH, and occurs in multiple forms–isoenzymes in the liver, intestines, and bone; AP hydrolyzes phosphate esters, yielding alcohol and phosphate; because ↑ total AP indicates either liver or bone disease, additional clinical studies–eg, evaluation of AP isoenzymes, are required to determine the cause of the elevation Physiologic ↑ in AP: During bone growth, infants, children and adolescents-levels are 3-fold > than adults, pregnancy, hepatobiliary disease–eg viral hepatitis, severe biliary obstruction, biliary cirrhosis, intrahepatic cholestasis, Paget's disease of bone, osteomalacia, osteogenic sarcoma, bone metastasis, hyperparathyroidism, infectious mononucleosis, vitamin D deficiency rickets; ↓ in hypoposphatasia, protein deficiency, magnesium deficiency Ref Range AP ranges differ according to method and lab. See Alkaline phosphatase isoenzyme, Immunoperoxidase.