Heart, acid phosphatase

Acid phosphatase (acid phosphomonoesterase, EC 3.1.3.2) also catalyzes the hydrolysis of phosphoric acid monoesters but with an acidic pH optimum. It has broad specificity and catalyzes transphosphorylations. Acid phosphatases are a quite heterogeneous group with monomeric, dimeric, larger glycoprotein, and membrane-bound forms. Acid phosphatase activity is present in the heart, liver, bone, prostate, and seminal fluid. Prostate carcinomas produce large quantities of acid phosphatase, and the enzyme is, therefore, used as a biomarker [141]. 

Beckman et al. (28) have studied the electrophoretic separation of the acid phosphatase activity in tissue extracts on starch gel at pH 8. They described four electrophoretic bands A, B, C, and D. Table IV (28) shows the distribution of activity in different organ extracts. The ABD pattern predominated in kidney BD in liver, intestine, heart, and skeletal muscle B in skin and D in pancreas. The C component was present in a large number of placentae but not in other adult organs. All four electrophoretic components were inhibited by d-(- -)-tartrate A contained sialic acid, D had a lower pH optimum and was more heat resistant than A, B, and C. Components C and D showed parallel electrophoretic behavior. In human skin fibroblasts grown in tissue culture, the acid phosphatase was generally high and the most common pattern was BD. Almost every culture showed some activity. The BD... 

BIO) carried out starch gel electrophoretic studies in 1200 individual placentas and in extracts of seven different organs obtained at autopsy from 14 individuals. The tissues showed different combinations of one or more bands of four distinct and, in some respects, biochemically different, acid phosphatase components. These were designated as A, B, C, and D in order of decreasing anodal mobilities. For example, in the case of heart tissue one individual showed three bands, ABD, whereas the remaining 13 showed a combination of two bands, BD. With regard to kidney tissue, 13 individuals had a combination of ABD, and one individual had a pair, BD. 

Schoenfeld, M. R., Increased serum acid phosphatase after arterial embolism. Amer. Heart J. 67, 92-94 (1964). 

Lactate dehydrogenase (human isoenzyme) Prostatic acid phosphatase (hmnan prostate) Alanine aminotransferase (pig heart) r a-Amylase (human pancreas)... 

Acid phosphatase Prostate, kidney, liver, heart... 

Different behaviour of the isoenzymes towards different substrates (e.g. the specificity of heart LDH for hydroxy-butyrate), different inhibitors (e.g. formaldehyde stable acid phosphatase) or heat inactivation (e.g. placental alkaline phosphatase). 

Acid phosphatase and /3-glucuronidase were particulate bound and detergent activated, indicating the existence of lysosomes in heart and skeletal muscle. Single or multiple doses of cortisone acetate had no significant effect on any of the enzyme measurements (Buchanan and Schwartz, 1967). 

In whole blood, phosphatase activity is associated primarily with red blood cells, but it is recognized that blood has a low phosphatase activity compared to other tissues such as the kidney, brain, liver, lung, and heart ([87] [88] and refs. cit. therein). Thus, studies with blood preparations should underestimate the in vivo rate of hydrolysis of phosphoric acid esters, a point of significance in the development of phosphate prodrugs. 

Two immunosensors developed by O Regan et al. [89,90] have demonstrated their usefulness for the early assessment of acute myocardial infarction (AMI). Human heart fatty-acid binding protein (H-FABP) is a biochemical marker for the early assessment of AMI. The authors constructed an amperometric immunosensor for the rapid detection of H-FABP in whole blood. The sensor is based on a one-step, direct sandwich assay in which the analyte and an alkaline phosphatase (AP) labelled antibody are simultaneously added to the immobilized primary antibody, using two distinct monoclonal mouse anti-human H-FABP antibodies. The substrate p-amino-phenyl phosphate is converted to p-aminophenol by AP, and the current generated by its subsequent oxidation at +300 mV vs. Ag/AgCl is measured. The total assay time is 50 min, and the standard curve was linear between 4 and 250 ng ml . The intra- and inter-assay coefficients of variation were below 9%. No cross-reactivity of the antibodies was found with other early cardiac markers, and endogenous substances in whole blood did not have an... 

Hucho, R Randall, D.D. Roche, T.E. Burgett, M.W. Pelley, J.W. Reed, L.J. a-Keto acid dehydrogenase complexes. XVII. Kinetic and regulatory properties of pyruvate dehydrogenase kinase and pyruvate dehydrogenase phosphatase from bovine kidney and heart. Arch. Biochem. Biophys., 151, 328-340 (1972)... 

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