Lysine plasma concentration

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... 

Table 19.2 Plasma concentration reference ranges for arginine, lysine, and tryptophan for patients with GA-1...

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. 

Spielmann, J., Noatsch, A., Brandsch, C., Stangl, G. L, and Eder, K. (2008). Effects of various dietary arginine and lysine concentrations on plasma and liver cholesterol concentrations in rats. Ann. Nutr. Metab. 53(3 ), 223-233. 

Taking into account the fact that carbonyl groups in blood plasma proteins are generated upon interaction of oxygen with histidine, arginine, lysine, and prohne, their concentration could be used as an indicator of oxidative stress. The data presented in Table 21.7 provide evidence of the systemic action of Enterosgel directed at mitigation of oxidative stress. 

A model system demonstrating the nutritional destruction of lysine in bovine plasma albumin (BPA) by reaction with either a dialdehyde (MA) or a keto-aldehyde (MGA) was studied in relation to reaction rates as affected by pH, temperature, reaction time and carbonyl concentration. The BPA was Fraction V obtained from Schwartz/Mann and had a molecular weight of 69 x 103 with sixty lysine residules/mole, an assayed content of 11.4%. It was dissolved in 0.0200 M phosphate-citrate buffer adjusted to the desired pH. Malonaldehyde was prepared by acid hydrolysis of its bis-(dimethyl acetal). An aqueous solution of pyruvic aldehyde was diluted with distilled water and phosphate-citrate buffer to give an MGA solution of the desired pH (16). 

The RDA for biotin has not been established. The requirement for biotin has been established as 30 to 100 pg/day. Biotin is produced by the gut microflora, which, it has been estimated, supplies half of our requirement. The rate of transport of free biotin by the gut cell is higher in the jejunum than in the ileum and is very low in the colon. Despite the low level of transport in the colon, it is apparently sufficient to allow supply by vitamin produced in the gut. The digestion of dietary proteins results in the release of the constituent amino acids and of biotin in the form of lysyl-biotin. Lysyl-biotin is further cleaved to lysine and biotin by biotinidase, an enzyme of the gut mucosa. The enzyme is present in milk and in the bloodstream as well, Biotin in human blood plasma occurs at a concentration of about 4 nM (Velazquez ef /, 1995). Nearly all of the biotin in human milk is free and not bound to proteins. Breast milk contains biotin at concentrations of about 25 nM (MiKik et al., 1997a),... 

Fructosamine is the generic name for plasma protein ketoamines (for reviews, see Armbruster and Hill et aT ). The name refers to the structure of the ketoamine rearrangement product formed by the interaction of glucose with the -amino group on lysine residues of albumm. Analogous to GHb, measurement of fructosamine maybe used as an index of the average concentration of blood glucose over an extended period of time. 

AVP is formed by neuronal cells of hypothalamic nuclei and stored in the neurohypophysis. In humans, it contains arginine at position 8. (In pigs, lysine is found at position 8.) AVP stimulates contraction of the muscles of capillaries and arterioles, raising blood pressure promotes contraction of the intestinal musculature, increasing peristalsis exerts contractile influence on the uterus and has a specific effect on the epithelial cells of renal collecting tubules, augmenting resorption of water independently of solutes to cause concentration of urine and dilution of blood serum. Its rate of secretion is regulated chiefly by the osmolarity of the plasma. 

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