Phosphorus metabolism, effects

Based on limited epidemiologic evidence, fluoride supplements, with or without calcium, estrogen and vitamin D, are used by clinicians for the treatment of osteoporosis. However, knowledge of the effects of fluoride on calcium and phosphorus metabolism in normal animals is limited although Spencer et al. (32) reported that ingestion of fluoride by three osteoporotic men did not affect calcium absorption but caused a decrease in urinary excretion. Moreover, there is a need to determine the long-term effects of fluoride treatment on bone strength and on soft tissues ( ). 

Sutherland, E.W. (1952). The effects of epinephrine and the hyperglycemic factor on liver and muscle metabolism in vitro. In Phosphorus Metabolism. (McElroy, W.D. Glass, B., Eds.), Vol. 2, pp. 577-593. The Johns Hopkins Press, Baltimore. 

Spencer, H., Kramer, L., Norris, C. and Osis, D. 1982B. Effect of small doses of aluminum-containing antacids on calcium and phosphorus metabolism. Am. J. Clin. Nutr. 36, 32-40. 

Ondreicka R, Ginter E, Kortus J. 1966. Chronic toxicity of aluminum in rats and mice and its effects on phosphorus metabolism. Br J Ind Med 23 305-312. 

No studies on body burden reduction methods were located. The state of definitive knowledge of white phosphorus metabolism is too limited to permit extensive speculation on methods for reducing body burden. However, it is possible that increasing selective excretion of phosphate may increase the rate of inorganic conversion of white phosphorus to phosphate (this conversion is described in detail in Section 2.3). Since phosphate is a naturally occurring component of the blood s buffering system, this would effectively deactivate the phosphorus. No methods for selectively increasing phosphate excretion were located. 

Figure 8.4 Effects of addition of P to a previously starved culture on the activity of phosphorus-metabolizing enzymes in E. coli (1) alkaline phosphatase (2) exopolyphosphatase (3) tripolyphosphatase (4) 1,3-DPGA-polyphosphate phosphotransferase (5) polyphosphate kinase (all in an P -free medium) (l -5 ) with the addition of P . The time of P addition is shown by the arrows (Nesmeyanova et al., 1974a).

I. S. Kulaev, V. I. Mel gunov andL. A. Yakovleva (1970d). The effect of 8-azaadenine on phosphorus metabolism in adenine-deficient mutants of Neurospora crassa (in Russian). Dokl. Akad. Nauk SSSR, 194, 1202-1205. 

A. V. Shnyreva and I. S. Kulaev (1994). Effect of Vesicular-Arbuscular Mycorrhiza on phosphorus metabolism in agricultural plants. Microbiol. Res., 149, 1-5. 

G. N. Zaitseva, A. N. Belozersky and L. P. Novozhilova (1960b). The effect of the the calcium ion on nitrogen and phosphorus metabolism in Azoiohacier vinelandii (in Russian). Mikrobiologiia, 29, 343-350. 

Plesnicar, M. 1983. Study of sulfur dioxide effects on phosphorus metabolism in plants using 32P as an indicator. Int. J. Appl. Radiat. Isot. 34 833-835. 

Kl. Kenny, A. D., and Heiskell, C. A., Effect of crude thyrocalcitonin on calcium and phosphorus metabolism in rats. Proc. Soc. Expil. Biol. Med. 120, 269-271... 

M24. Moseldlde, L., Christensen, M. S., Melsen, F., and Sorensen, N. S., Effect of antithyroid treatment on calcium-phosphorus metabolism in hyperthyroidism. I. Chemical quantities in serum and urine. Acta Endocrinol. 87, 743-750 (1978). 

F8. Freinkel, N., Pathways of thyroidal phosphorus metabolism The effect of pituitary thyrotropin upon phospholipids of the sheep thyroid gland. Endocrinology 61, 448-460 (1957). 

Figure 42-2. Some effects of vitamin D (D), parathyroid hormone (PTH), and calcitonin (CT) on calcium and phosphorus metabolism. Vitamin D increases absorption of calcium from both gut and bone, while PTH increases reabsorption from bone. Both vitamin D and parathyroid hormone reduce urinary excretion ot calcium. (Reproduced, with permission, from Katzung BG [editor] Basic Clinical Pharmacology, 8th ed. McGraw-Hill, 2001.)...

The absorption of calcium, sodium, potassium, chloride, magnesium, and iron is thought to be influenced by the thyroid hormone. The results of the studies of the effect of thyroxine on electrolyte metabolism are often contradictory and difficult to interpret however, it seems accepted that thyroxine affects phosphorus metabolism by increasing the excretion of the metal in both urine and stools. 

The effect of insulin on phosphorus metabolism in muscle was studied in three ways the incorporation of radioactive phosphorus in various phosphorylated compounds, balance studies in isolated diaphragms in which inorganic total phosphorus and labile phosphorus were measured as well as the rate of glycogen synthesis, and in vitro phosphorylation studies of creatine. 

Hart, L.E. and DeLuca, H.E. 1985. Effect of vitamin Dj metabolites on calcium and phosphorus metabolism in chick embryos. Am. J. Physiol. 248 E281-5. 

The inclusion of factors under this heading has been made with some reservation, as it is obvious that conditions which induce profound disturbance of any vital metabolism may have indirect influence upon others. We have, therefore, included only those factors which appear to have a well-defined effect, either direct or indirect, upon calcium and phosphorus metabolism. 

This hormone is secreted by the parathyroid glands, which are four in number and lie on the posterior surface of the thyroid gland. The exact manner in which the hormone exerts its action upon calcium and phosphorus metabolism has not been proved satisfactorily, but the most immediate effect of administration of parathyroid extract which has been generally observed is an increased excretion of phosphorus in the urine, which is accompanied by a lowering of the serum inorganic phosphate. The increase in the urinary phosphate excretion has been ascribed by Harrison and Har-... 

The beneficial effect of vitamin D upon calcium absorption has already been noted and is usually stressed as the major action of this vitamin upon calcium and phosphorus metabolism. There is considerable evidence, however, of further effect upon this metabolism within the body, but its precise nature is still a subject for speculation. 

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