Calcium phospholipids

Activated partial thromboplastin time aPTT is performed by adding calcium phospholipids and kaolin to citrated blood and measures the time required for a fibrin clot to form. In this manner, aPTT measures the activity of intrinsic and common pathways. Prolongation of aPTT may be due to a deficiency or inhibitor for factors II, V, VIII, IX, X, XI, and XII. It also may be due to heparin, direct thrombin inhibitors, vitamin K deficiency, liver disease, or lupus anticoagulant. 

Sakane, R, Yamada, K., Imai, S., and Kanoh, H., 1991, Porcine 80-kDa diacylglycerol kinase is a calcium-binding and calcium/phospholipid-dependent enzyme and undergoes calcium-dependent translocation./.B/o/. Chem. 266 7096-7100. 

Boskcy, A. L., Posner, A. S. Extraction of a Calcium-Phospholipid-Phosphatc Complex from Bone. Calc. Tiss. Res. 19, 273 (1976)... 

Perisic, O., Fong, S., Lynch, D.E., Bycroft, M., and Williams, R.L., 1998, Crystal structure of a calcium-phospholipid binding domain from cytosolic phospholipase A2. J. Biol. Chem. 273 1596-1604. 

Structure of the first C2 domain of synaptotagmin I a novel calcium/phospholipid-binding fold. Cell 80 929-938. 

Protein kinase C (a, pi, pil, y, 5, s) Calcium, phospholipids diacylglycerols Calphostin C... 

Boyan BD, Boskey AL Co-isolation of proteolipids and calcium-phospholipid-phosphate complexes. Calcif Tissue Int 1984 36 214-218. 

Other Reactions of Phospholipids. The unsaturated fatty acid groups in soybean lecithin can be halogenated. Acetic anhydride combined with the amino group of phosphatidylethanolamine forms acetylated compounds. PhosphoHpids form addition compounds with salts of heavy metals. Phosphatidylethanolamine and phosphatidjhnositol have affinities for calcium and magnesium ions that are related to interaction with their polar groups. 

Mammals synthesize phosphatidylserine (PS) in a calcium ion-dependent reaction involving aminoalcohol exchange (Figure 25.21). The enzyme catalyzing this reaction is associated with the endoplasmic reticulum and will accept phosphatidylethanolamine (PE) and other phospholipid substrates. A mitochondrial PS decarboxylase can subsequently convert PS to PE. No other pathway converting serine to ethanolamine has been found. 

A 0-9% salt solution is considered to be isotonic with blood. Other electrolytes present include bicarbonate ions (HCOj ) and small amounts of potassium, calcium, magnesium, phosphate, sulphate and organic acid ions. Included among the complex compounds and present in smaller amounts are phospholipids, cholesterols, natural fats, proteins, glucose and amino acids. Under normal conditions the extracellular body fluid is slightly alkaline with a pH of 7-4. ... 

The different pro- and anticoagulatory systems are complex regulated cascades involving blood cells (platelets, monocytes, endothelial cells), enzymes, cofactors, phospholipids, and calcium, which interact with each other... 

In the case of prothrombin and related clotting factors, interruption of the vitamin K cycle leads to the production of nonfunctional, undercarboxylated proteins, which are duly exported from hepatocytes into blood (Thijssen 1995). They are nonfunctional because there is a requirement for the additional carboxyl residues in the clotting process. Ionized carboxyl groups can establish links with negatively charged sites on neighboring phospholipid molecules of cell surfaces via calcium bridges. 

Angiotensin II binds to specific adrenal cortex glomerulosa cell receptors. The hormone-receptor interaction does not activate adenylyl cyclase, and cAMP does not appear to mediate the action of this hormone. The actions of angiotensin II, which are to stimulate the conversion of cholesterol to pregnenolone and of corticosterone to 18-hydroxycorticosterone and aldosterone, may involve changes in the concentration of intracellular calcium and of phospholipid metabolites by mechanisms similar to those described in Chapter 43. 

The lipid in muscle is composed primarily of triglycerides (depot fats) and of phospholipids (membrane components), and is a constituent which varies enormously not only in amount present, but also in properties such as degree of saturation (species dependent). The ash of lean meat is comprised of various minerals such as phosphorus, potassium, sodium, magnesium, calcium, iron and zinc Carbohydrate was not noted in the proximate composition because while some may be present, it is normally there in low concentration compared to the other constituents. Glycogen is the carbohydrate occurring in greatest concentration in muscle but is normally degraded soon after the animal is sacrificed. 

Burton, K.P., Morris, A.C., Massey, K.D., Buja, L.M. and Hagler, H.K. (1990). Free radicals alterionic calcium levels and membrane phospholipids in cultured rat ventricular myocytes. J. Mol. Cell. Cardiol. 22, 1035-1047 (abstract). 

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