Glycerophosphates liver

Alkaline phosphatase assays based on 3-glycerophosphate now appears to be obsolete, and methods buffered by either glycine or barbital are also obsolete as these buffers inhibit ALP or are poor buffers. Serum alkaline phosphatase is known to be composed of several isoenzymes which presumably arise from bone, liver, intestine, and placenta. The placental alkaline phosphatase is known to be much more resistant to heat denaturation than the other isoenzymes, and this resistance provides a simple test for it (5). The other enzymes can be separated through the differential inhibition by phenylalanine, by electrophoresis and by specific antibodies. However, the clinical usefulness of the results obtained is in doubt (23). 

In 1924, Martland et al. (1) reported on phosphatase activity in red blood cells. Roche later differentiated between the phosphatase of the red cells with pH optimum 6.0-6.2 and the phosphatase from white cells with optimum 8.8-9.0. Roche also showed that a-glycerophosphate was split more rapidly than -glycerophosphate by red cell extracts while the reverse was true of acid phosphatase activity in plasma (2). While studying the source of acid phosphatase activity in male urine, Kutscher and Wolberg discovered the very high activity of acid phosphatase in human prostate (3). This tissue was shown by Woodard to have one-thousand times the activity of extracts from bone, liver, and kidney (3a). Igarashi and Hollander crystallized the acid phosphatase of rat liver and showed that under certain conditions allosteric control of the activity could be demonstrated (4). 

Krebs and Woodford (72) have reported the activity of FDPase to be much lower than that of phosphofructokinase in muscle, but it has been estimated by Salas et al. (71) that in view of the relative mass of muscle tissue, the total FDPase activity of muscle was equivalent to that of liver. It was proposed by Krebs and Woodford (72) that the enzyme might play a role in the reconversion of a-glycerophosphate to carbohydrate since this substance was found to accumulate in significant quantities in muscle. This hypothesis has been examined in detail by... 

Ovalbumin Conalbumin Ovomucoid Lysozyme Vitellogenin apo-VLDL Glucose-6-P-dehydrogenase Oviduct Oviduct (liver) Oviduct Oviduct Liver Liver Uterus Thyroid Hormones Carbamyl phosphate synthase Growth hormone Prolactin ( ) a-Glycerophosphate dehydrogenase Malic enzyme Liver Pituitary Pituitary Liver (mitochondria) Liver... 

The FAD-requiring enzymes in mammalian systems include the D- and L-amino acid oxidases, mono- and diamine oxidases, glucose oxidase, succinate dehydrogenase, a-glycerophosphate dehydrogenase, and glutathione reductase. FMN is a cofactor for renal L-amino acid oxidase, NADH reductase, and a-hydroxy acid oxidase. In succinate dehydrogenase, FAD is linked to a histidyl residue in liver mitochondrial monoamine oxidase, to a cysteinyl residue. In other cases, the attachment is nonco-valent but the dissociation constant is very low. 

The measurement of oxygen uptake provides a direct index of metabolic rate this measurement can be done simply by placing experimental animals In a calibrated vessel maintained at constant temperature and connected to an oxygen analyzer (86). Repeatedly used as an Index of thyromimetic activity have been the in vitro assay of oxygen uptake by suspended mitochondria and the spectrophotometric assays of rat liver mitochondrial a-glycerophosphate dehydrogenase (87) and of cytoplasmic malic enzyme (88). 

This compound, prepared by Benson et al. (109), was found to be indistinguishable from T3 in oxygen uptake and glycerophosphate activity tests and to be half as active as T3 in displacing labeled T3 from rat liver nuclei in specific in vivo conditions. 

Daae, L.N.W. Bremer, J. 1976) Biochim. Biophys. Acta, 210, 92-104. The aeylation of glycerophosphate in rat liver. A new assay procedure for glycerophosphate acylation, studies on its subcellular and submitochondrial localization and determination of the reaction products. 

I ( ) reported that the signs of nickel deprivation in chicks included depressed levels of liver phospholipids, oxidative ability of the liver in the presence of a-glycerophosphate, yellow lipochrome pigments in the shank skin, hematocrits and ultrastructural abnormalities in the liver. 

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