alkaline phosphatase

(redirected from ALK PHOS)
Also found in: Acronyms, Encyclopedia, Wikipedia.

alkaline

 [al´kah-līn]
1. having the reactions of an alkali.
2. having a pH greater than 7.0.
alkaline phosphatase an enzyme localized on cell membranes that hydrolyzes phosphate esters liberating inorganic phosphate and has an optimal pH of about 10.0. 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.

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.

al·ka·line phos·pha·tase

a phosphatase with an optimal pH higher than 7, present ubiquitously; localized cytochemically in membranes by modifications of Gomori nonspecific alkaline phosphatase stain; it hydrolyzes many orthophosphoric monoesters; low levels of this enzyme are seen in cases of hypophosphatasia.

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.
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.

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.

alkaline phosphatase

A 69-kD homodimeric metalloenzyme, EC 3.1.3.1, 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. Alkaline phosphatase (AP) hydrolyses phosphate esters, yielding alcohol and phosphate; because increased total AP indicates either liver or bone disease, additional clinical studies, such as evaluation of AP isoenzymes, are required to determine the cause of the elevation.
 
Physiologic increase in AP
During bone growth: infants’, children’s and adolescents’ levels are 3-fold > than adults; pregnancy.

Pathologic increase in AP
Hepatobiliary disease (e.g., 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.

Decreased AP
Hypoposphatasia, protein deficiency, magnesium deficiency.
 
Ref Range
AP ranges differ according to method and lab.

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.

al·ka·line phos·pha·tase

(al'kă-lin fos'fă-tās)
A phosphatase with an optimal pH of above 7.0 present in many tissues; low levels of this enzyme are seen in cases of hypophosphatasia.

Alkaline phosphatase

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

alkaline phosphatase

an enzyme marker of bone formation; levels are raised in active Paget's disease

al·ka·line phos·pha·tase

(al'kă-lin fos'fă-tās)
A phosphatase with an optimal pH of above 7.0 present in many tissues; low levels of this enzyme are seen in cases of hypophosphatasia.

alkaline

having the reactions of an alkali.

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.

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.

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.