Albumin concentration in plasma

Albumin is the major plasma protein and is synthesized and secreted by the liver. It accounts for about. S09F of the total hepatic proiein production. Albumin has a biological half-life in plasma of about 20 days and a significant decrease in albumin concentration in plasma is slow to occur if there is reduced synthesis. Albumin makes the biggest contribution to the plasma... 

Albumin concentration in plasma Markedly low Normal or slighlly low... 

Kwashiorkor— The specific features which distinguish this disorder from marasmus are (1) a significantly subnormal albumin concentration in plasma, (2) swollen parotid glands (just under and in front of the ears), (3) a depressed ratio of essential to nonessential amino acids in the blood plasma, (4) fatty liver (which often may be palpated, and (5) a moderate deficit in weight for height and age (the weight is usually 80% or more of normal). 

This pattern of results is typical of hepatocellular damage (necrosis). The high activity of AST and ALT are due to leakage from damaged cells the normal albumin value indicates that this is an acute (recent) condition. The modest rise in bilirubin concentration in plasma is not itself diagnostic at this stage. 

Drug distribution in elderly patients may be altered by hypoalbuminemia, qualitative changes in drug-binding sites, reductions in relative muscle mass, increases in the proportion of body fat, and decreases in total body water. The plasma level of free, active drug is often a direct function of the extent of drug binding to plasma proteins. There is a well-documented age-dependent decline (about 20%) in plasma albumin concentration in humans due to a reduced rate of hepatic albumin... 

Hypoproteinemia may result in low levels of serum calcium, ceruloplasmin, and transferrin. Because losses of iron are at most 0.5-1.0 mg/24 hr, even with the heaviest proteinuria, other factors must operate to produce iron deficiency and microcytic hypochromic anemia. Although the copper-binding protein ceruloplasmin is lost in the urine in nephrotic subjects and its plasma levels are low, plasma and red cell copper concentrations are usually normal. Zinc circulates mainly bound to albumin and also to transferrin, and thus the reported reduction zinc concentration in plasma, hair, and white cells in nephrotic patients is not surprising. 

Over 20,000 samples of microbial culture broths were subjected to our screening program for CETP inhibitors by method A. At first no BSA was added to the assay mixture, but many false-positive compounds such as fatty acids were isolated. To prevent this, the optimal concentration of BSA was tested and set up as 200 pM, resulting in a low hit rate in the primary screen. The serum albumin concentration in the assay is similar to that in human plasma. Finally, we discovered erabulenols from a fungal strain, and ferroverdins from an actinomycete strain, as novel CETP inhibitors (Fig. 5). 

In addition to factors Influencing luminal uptake of zinc, transfer across the basolateral membrane has been shown to be dependent on the concentration of albumin in the portal circulation (33). These investigations suggest that metabolic factors which affect the albumin concentration in the plasma may also affect the rate of portal zinc transfer. It should be noted that EDTA did not enhance zinc accumulation within the mucosal cells yet it Increased transfer to the vascular perfusate. These results suggest that basolateral membrane transport of zinc is enhanced by EDTA. We have proposed (35), as has Davies (38), that basolateral transport to the circulation is the rate limiting phase of zinc absorption. Since EDTA and zinc might be transported as a complex (42), the latter may transverse this barrier more easily and thus Increase zinc absorption. 

As shown in Table 7.1, the total riboflavin concentration in plasma is very much lower than in most tissues. About 50% of plasma riboflavin is free riboflavin, which is the main transport form, with 44% as FAD and the remainder as riboflavin phosphate. The vitamin is largely protein bound in plasma free riboflavin binds to both albumin and a- and /3-globulins, and both riboflavin and the coenzymes also bind to immunoglobulins. The products of photolysis of riboflavin bind to albumin with considerably higher affinity than riboflavin itself this albumin binding may represent a mechanism to prevent tissue... 

Immediately after an injury, there is loss of fluid to extravascular tissue with a resulting decrease in plasma volume. If the decrease is enough to impair circulation, glomerular filtration is diminished. Diminished renal function leads to the accumulation of urea and other end products of protein metabolism in the circulation. In burned patients, serum total protein concentration falls by as much as 0.8g/dL became of both loss to extravascular spaces and catabolism of protein. Serum aj-, tt2-, and y-globulin concentrations increase, but not enough to compensate for the reduced albumin concentration. The plasma fibrinogen concentration responds dramatically to trauma and may double in 2 to 8 days after surgery. The concentration of C-reactive protein rises at the same time. 

The level of plasma albumin-bound fatty acids increases when lipolysis rates are high. The tissue uptake of fatty acids is proportional to their concentration in plasma and is therefore largely dependent on blood flow. During intense exercise, the flow of blood through the splanchnic bed is reduced and more fatty acids are available to skeletal muscle. With the exception of nerve tissue and blood cells, tissues can use fatty acids by /3-oxidation and by the TCA cycle. Fatty acid uptake is not regulated by hormones or intracellular effectors. Free fatty acids readily diffuse across the plasma membrane of cells where they are used strictly in response to supply and demand. This is illustrated for cardiac muscle in Figure 22-20. 

Schurr et al.43 reported the amino acid concentrations in various tissues of the rat. Using these data to calculate tissue-to-plasma ratios, it becomes apparent that the relative availability of plasma tryptophan to tissues is much less than that of other amino acids. The finding, described elsewhere, that tryptophan in serum or plasma can be present as free and bound (to plasma albumin) is unique among amino acids,44 and this further limits or controls the availability of tryptophan from the blood to organs or tissues, especially the brain. Tryptophan differs from other amino acids in that its concentration in plasma of rats increases (30 to 40%) after fasting, after insulin administration, or after consuming a carbohydrate meal.45... 

From the available data, it appears that cholephilic dyes must be water soluble and noncolloidal. Anionic dyes, regardless of their chemical structure, are excreted by the liver more readily than cationic dyes (H19). Many dyes are bound to plasma albumin, and it has been suggested that those which are more strongly bound are secreted by the liver whereas those which are more loosely bound are excreted by the kidney (B17). Thus, at a concentration in plasma of 1 mg/100 ml, about 20% of phenol red is not protein bound whereas less than 1% of BSP is dialyzable. 

Oncotic pressure (or colloid osmotic pressure) is the osmotic pressure that results from the difference between the protein (mainly albumin) concentrations of plasma and the interstitial fluid. Water is lost from the body via feces, urine, salivation, insensible respiration, and through the skin, with sensible perspiration of sweat occurring in a few species. Although the movement of proteins between spaces is restricted, water and small ions can move across permeable membranes between the spaces. The volume of ECF is highly dependent on its sodium concentration and, under physiological conditions, the sodium ion concentrations of plasma and interstitial fluids are similar. 

These agents are rapidly but incompletely absorbed from the G1 tract (30-80%). As absorption is more efficient on an empty stomach, they ideally are administered 1 hour before or 2 hours after meals. Peak concentrations in plasma are attained by 1 hour. They all are highly bound to plasma albumin (>90%) none is removed from the circulation to a significant degree by hemodialysis. 

In evaluation of the response of living organisms to resveratrol, it is important to determine the capacity of gastrointestinal absorption and the distribution of resveratrol to various target tissues as well as its metabolism. The bacterial microflora in the ileum and cecum plays an important role in the metabolism and absorption of resveratrol. Kinetics of trans- and civ-resveratrol (3,4, 5-trihydroxystilbene) after oral administration of red wine in rats showed that a fraction of resveratrol (6.5mg/l) was absorbed by rats and can be detected in considerable concentrations in plasma. Peak tissue concentrations recorded at cardiac tissue, liver, and kidneys.A recent study reported albmnin as one of the plasmatic carriers of resveratrol. Interaction of resveratrol with albumin is essential for the transporting of the compoimd in blood circulation and the delivery of resveratrol at the cell surface before cell membrane uptake. ... 

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