Phosphate critical role

Normally, the number of anions and cations in each fluid compartment are equal. Cell membranes play the critical role of maintaining distinct ICF and ECF spaces which are biochemically distinct. Serum electrolyte concentrations reflect the stores of ECF electrolytes rather than that of ICF electrolytes. Table 24-4 lists the chief cations and anions along with their normal concentrations in the ECF and ICF. The principal cations are sodium, potassium, calcium, and magnesium, while the key anions are chloride, bicarbonate, and phosphate. In the ECF, sodium is the most common cation and chloride is the most abundant anion while in the ICF, potassium is the primary cation and phosphate is the main anion. Normal serum electrolyte values are listed in Table 24—5. 

More than 99% of total body calcium is found in bone the remaining less than 1% is in the ECF and ICE Calcium plays a critical role in the transmission of nerve impulses, skeletal muscle contraction, myocardial contractions, maintenance of normal cellular permeability, and the formation of bones and teeth. There is a reciprocal relationship between the serum calcium concentration (normally 8.6 to 10.2 mg/dL [2.15 to 2.55 mmol/L]) and the serum phosphate concentration that is regulated by a complex interaction between parathyroid hormone, vitamin D, and calcitonin. About one-half of the serum calcium is bound to plasma proteins the other half is free ionized calcium. Given that the serum calcium has significant protein binding, the serum calcium concentration must be corrected in patients who have low albumin concentrations (the major serum protein). The most commonly used formula adds 0.8 mg/dL (0.2 mmol/L) of calcium for each gram of albumin deficiency as follows ... 

Brailoiu, E., Patel, S. and Dun, N. J. Modulation of spontaneous transmitter release from the frog neuromuscular junction by interacting intracellular Ca2+ stores critical role for nicotinic acid-adenine dinucleotide phosphate (NAADP). Biochem. J. 373 313-318, 2003. 

The intracellular CER concentration results from the equilibrium between CER production and CER metabohsm It now appears that CER metabolism plays a critical role in regulating intracellular CER concenttation and therefore effector-induced cytotoxicity. The four major CER metabolic pathways include its reconversion into SM, its catabohsm to sphingosine (followed by sphingosine 1-phosphate) and its metabolism to glucosylceramide or galactosylceramide. All of which may conttibute to limiting stress-induced CER elevation, except for the galactosylceramide pathway which has of yet not been described. 

Chemically, it is a challenge to design phosphate receptors. Also, it is of interest to see if the solid-state sapphyrin phosphate structures reflect events in solution. On the biological side, phosphate anions play critical roles in numerous metabolic and energy transduction processes.Also, phosphate entities are present in the active forms of many antiviral agents. ... 

Regulation of Sucrose Synthesis In the regulation of sucrose synthesis from the triose phosphates produced during photosynthesis, 3-phosphoglycerate and P, play critical roles (see Fig. 20-26). Explain why the concentrations of these two regulators reflect the rate of photosynthesis. 

Anions, such as fluoride, chloride, and phosphate, play critical roles in a range of biological processes and are implicated in a number of diseased states, ranging from fluorosis to cystic fibrosis [41]. Therefore, the exploitation of new luminescent chemosensors for anions is very important. The main design approach for lanthanide complexes as luminescent chemosensors for anions is to utilize the specific interaction between the anions and the lanthanide ion to realize the detection of the anions. 

As has been discussed in relation to sulfate conjugation, there is increasing evidence that phosphate formation may play a critical role in regulating insect steroids this is particularly true for steroids present in eggs and during early stages of embryonic development. 

The kidney plays a critical role in calcium homeostasis. PTH acts directly on the kidney to suppress calcium ion excretion in the urine by maximizing tubular calcium reabsorption. It increases phosphate ion excretion in the kidney (phosphaturic effect) to prevent excessive accumulation of this anion released during bone demineralization. 

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