Free and peptide hydroxyproline in chronic uremia

4-(5,6-Dimethoxy-2-phthalimidinyl)-2-methoxyphenylsulfonyl Chloride as a Fluorescent Labeling Reagent for Determination of Amino Acids in High-Performance Liquid Chromatography and Its Application for Determination of Urinary Free Hydroxyproline

“…When the concentrations of Hyp in hydrolysed urine (total Hyp) were measured according to the method reported previously (17), the concentration ratio of free Hyp to total Hyp was 0.006 -0.028 (mean Ϯ SD; 0.015 Ϯ 0.0086). The mean value was similar to the value (0.012) reported previously (19).…”

“…For determination of urinary free Hyp, some studies using a colorimetric method (19), HPLC (20,21), and flow injection analysis (22) have been reported. However, these methods required large sample volumes because the sensitivities were very low.…”

Biochemistry of the Hydroxyprolines

“…In some severe cases free hydroxyproline constitutes nearly 35% of the total hydroxyproline (276,361,362). In Paget's disease even though there is a tremendous increase in the total urinary hydroxyprolinc the excretion of free hydroxyproline is not increased.…”

Amino Acid and Keto Acid Diets for Therapy in Renal Failure

“…This is an important consideration because the diets prescribed in this condition often do not con tain a surfeit of all essential amino acids. More over, in renal failure there are alterations in the metabolism of a number of essential and nonessential amino acids, including trypto phan [63], phenylalanine [64-66], tyrosine [66,67], citrulline [68], hydroxyproline [69], and valine [70], and such abnormalities may affect dietary requirements. Bergstrom el al.…”