Plasma lysine

Plasma lysine The concentration of free lysine in the portal plasma of rats was measured 45, 60, 75, 90, 12o, and 180 min after feeding a test meal of various selected proteins to... 

Comparison with in vivo procedures Although the FDNB procedure proved to be a suitable reference method, there is no doubt that all methods should be ultimately compared to in vivo procedures. For this reason selected samples were also analyzed by plasma amino acid and digestibility methods. Preliminary results ( Table II ) show that plasma lysine results correlated very well with results for lysine digestibility and FDNB lysine ( r =0.95 ), reasonably well with those for dansyl chloride lysine, succinic anhydride reactive lysine and dye binding lysine, but poorly with total lysine. Although the absolute values were in many cases very different, it is apparent that all methods except total lysine can be used to at least indicate the extent of lysine damage. 

Since one of the most important, if not the most important, result of a defect of the biosynthesis of urea is an increased level of blood ammonia, it is essential to consider other conditions that might affect indirectly the urea cycle or in some other way raise the blood ammonia. For example, it has been suggested that since lysine can act as a competitive inhibitor of the conversion of arginine to ornithine and urea, an increased level of plasma lysine may therefore inhibit the urea cycle (B12). 

Fractions of blood plasma Lysine, e-aminocaproic acid or heparin Sepharose 220... 

Saccharopine dehydrogenase (NADP, L-lysine-forming) (EC 1.5.1.8) and Saccharopine dehydrogenase (NAD, L-glutamate-forming) (EC 1.5.1.9). Elevated plasma lysine. (0.2-1.5 mmol/1). Increased urinary lysine, N-acetyllysine, homocitrulline and homo-... 

The digestion of protein within the horse occurs mainly in the fore gut through enzymic digestion in the stomach and small intestine, as described in Chapter 8. Amino acids produced from microbial protein synthesis in the hind gut are not absorbed in sufficient quantities to provide any meaningful contribution to amino acid supply. For example, studies that have infused lysine into the hind gut have shown no effect on plasma lysine levels and there is no active absorption of amino acids in the large intestine. 

Nitrogen-15 Enrichment in Plasma Lysine Application to Measurement of... 

Aminoadipic acid concentrations in the urine of the patients of Wilson et al. (1975) were 1480 /xmol (24 h) and 1500 /utmol (24 h) in his sister, compared to 520 fimol (24 h)" in the patient of Przyrembel et al. (1975) on a protein intake of 4.5 g per kg body weight (lysine 390 mg kg" ). The latter authors were able to demonstrate a greatly reduced excretion when protein intake and lysine intake were reduced, the 2-aminoadipic acid excretion falling to 155 tmol (24 h) on a protein intake of 2.3 g per kg body weight (lysine 170 mg/kg) and 49 /imol (24 h) on a protein intake of 2.3 g per kg body weight with a zero lysine intake. Controls excreted 21-29 /xmol (24 h) Przyrembel al. (1975) also showed the effects of an oral lysine load test with increased serum concentrations of both lysine and 2-aminoadipic acid. Baseline plasma lysine concentrations in their patient were low normal (0.062-0.194 mmol 1 S normal 0.227 0.091) and 2-aminoadipic acid concentrations were 0.050-0.079 mmol 1 (normal undetectable). 

Hyperargininemia. This defect is characterized by elevated blood and cerebrospinal fluid arginine levels, low erythrocyte levels of arginase (reaction 5, Figure 29-9), and a urinary amino acid pattern resembling that of lysine-cystinuria. This pattern may reflect competition by arginine with lysine and cystine for reabsorption in the renal tubule. A low-protein diet lowers plasma ammonia levels and abolishes lysine-cystinuria. 

The solubility of lysine derivative, 3.20, was measured at slightly over 180mg/mL, and molecular modeling also demonstrated potentially favorable plasma protein binding (Zsila et al. 2004). 

ROS can modify amino acid side chains, with histidine, tryptophan, cysteine, proline, arginine, and lysine among those most susceptible to attack (Brown and Kelly 1994). As a result, carbonyl groups are generated, and these carbonyl concentrations can be measured directly in plasma by using atomic absorption spectroscopy, fluorescence spectroscopy, or HPLC following reaction with 2,4-dinitrophenylhydrazine. 

The standard diet used in our experiments is a semipurified, cholesterol-free preparation that is composed of 25% protein, 40% sucrose, 13% coconut oil, 1% corn oil, 15% cellulose, 5% mineral mix, and 1% vitamin mix. This diet has been shown to induce an endogenous hypercholesterolemia and lead to atherosclerosis in rabbits and monkeys (4, 5). The specific question addressed by our series of investigations is whether the type of dietary protein, when all other dietary components are constant, can influence the development of hyperlipoproteinemia and atherosclerosis. More specifically, we have examined the effects of the individual amino acids, lysine and arginine, and their ratios in the diet on plasma and hepatic lipids as well as the development of arterial plaques. 

A T-C polymorphism was described in the sequence of apo(a)-KIV10 (V6), corresponding to nucleotide 12,605 of the published cDNA sequence (M24). This variant results in the substitution of a methionine (ATG) with a threonine (ACG) at this position. No correlation was observed between the polymorphism and plasma Lp(a) levels. Although the Met-Thr substitution is present within the lysine binding pocket in KIV10, its effect on lysine binding properties of this kringle remains to be determined. 

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