Phosphorus blood distribution

No quantitative information on absorption, distribution, metabolism, and excretion of white phosphorus following inhalation, oral, dermal, and dermal bum exposure was located. Studies in which 32P-labeled white phosphorus was orally administered to animals demonstrated that the label was widely distributed throughout the body, with some of the highest concentrations in the liver, kidney, blood, spleen, and brain (Cameron and Patrick 1966 Lee etal. 1975). 

Phosphorus is found in every cell of the body, but most of it (about 80% of the total) is combined with calcium as Ca3(P04)2 in the bones and teeth (Harper 1969 Tietz 1970). Phosphorus is present in cells mainly as organic phosphate, with a small amount in serum as inorganic phosphate (Tietz 1970). Phosphorus is involved in the intermediary metabolism of carbohydrates (Tietz 1970). About 10% is found in combination with proteins, phospholipids, and carbohydrates and in other compounds in the blood and muscle (Harper 1969). The remaining phosphorus is widely distributed in various chemical compounds such as nucleic acids, nucleotides, and adenosine triphosphate (ATP) (Tietz 1970). 

The recommended ratio of phosphorus to calcium is 1 1, except in infants it is 2 1. For older infants, the recommended intake of phosphorus is increased to 80% of the calcium requirement, so that the ratio is similar to cow s milk (Harper 1969). Both phosphorus and calcium are distributed similarly in foods, hence a sufficient intake of calcium ensures a sufficient intake of phosphorus. The exception is cows milk, which contains more phosphorus than calcium (Harper 1969). The adult daily requirement for phosphorus is about 700 mg. A balanced diet provides sufficient amounts of phosphorus because it is commonly found in foods (phosphoproteins and phospholipids, inorganic phosphate), especially milk and milk products, wheat, meats and fish (Latner 1975). In the body, normal serum (inorganic) phosphorus levels are 4-7 mg/100 mL in children and 3-4.5 mg/100 mL in adults and the elderly. In body fluids and tissues, normal serum phosphorus levels found are 40, 170-250, 360, and 22,600 mg/100 mL in blood, muscle, nerve, and both bones and teeth, respectively (Harper 1969 Tietz 1970). 

A normal adult has a total body phosphorus content of 700-800 g [1]. The majority of phosphate is present in bone, although approximately 15% is distributed outside of the skeleton where it is present in the form of inorganic phosphate in extra-cellular fluid and organic phosphates within cells, such as adenosine triphosphate (ATP), nucleic acids, and membrane phospholipids. As such, phosphorus plays a vital role in numerous cell processes including cell energetics, cell membrane formation, and DNA RNA synthesis, to name a few. Within blood, phosphate exists mainly in two forms, HPO and HjPO. These two anions are important serum buffers and their relative concentrations are determined by the serum pH. 

K13. Keating, F. R., Jones, J. D., Elveback, L. R., and Randall, R. V., The relation of age and sex to distribution of values in healthy adults of serum calcium, inorganic phosphorus, magnesium, alkaline phosphatase, total protein, albumin and blood urea. /. Lab. Clin. Med. 73, 825-834 (1969). 

McPhail, M.K. and Adie, P.A., The distribution of radioactive phosphorus in the blood and tissues of rabbits treated with tagged sarin. Can. J. Biochem. Physiol, 38, 945, 1960. 

These facts concerning the nature of thrombokinase just mentioned indicate the presence of a lipoid containing phosphorus or phosphatide, which is largely distributed in all organic extracts, as well as in the plates, and is also present in the leucocytes. This substance lacks all properties of enzymes. It is, however, indispensable in the process of the coagulation of blood. 

P/litre in cows milk) is distributed between more than 50 different compounds, both organic and inorganic. Most abundant and important of these are the casein phosphoproteins, calcium phosphates and the phospholipids. Other phosphorus compounds, present in much smaller quantities, are vitamins, various nucleic acids, enzymes, sugar phosphates and proteose peptones (phosphoglyco-peptides). Non-phosphorus compounds present at low levels include blood serum albumin, immune globulins, lactoferrin and ceruloplasmin. 

Riley, R. F. Metabolism of phosphorylcholine. II. Partition of phosphorylcholine phosphorus between blood phosphate fractions. III. Partition of phosphorylcholine phosphorus between tissues. IV. Distribution of phosphorylcholine phosphorus in tissue lipids. J. biol. Chem. 163, 535-49 (1944). 

Of the total calcium in the body, 99% is contained in bones and teeth, and if the tendons and ligaments are included the complete skeletal structure contains 99.5% of the body s calcium. The remaining 0.5% is distributed among the blood, the lymph, and the soft tissues in which the concentration varies somewhat but in general that of the tissues and lymph approximates to the diffusible calcium concentration of plasma. Variable estimates of the distribution of phosphorus suggest that rather more than 85% of the total phosphorus is combined with calcium in the skeleton, about 10% is in muscle tissue, rather less than 1% in brain, and about 0.3% in blood, the remainder being in other tissues and tissue fluids. The... 

The blood concentrations of Pi ions are higher early in life and then decline gradually until late life. The normal range for adults is 2.7-4.5 mg/dl (0.87-1.45mmol/l). The percentage distributions of the blood fractions of phosphorus compared to those... 

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