Peptides in human urine

Peptides in Human Urine (Skarzynski and Samecka-Keller), 5, 107 Protein Bound Iodine (Chaney), I, 82 Radioactive Iodine-131 in the Diagnosis of Hyperthyroidism, Blood Plasma Levels of (Silver), 1, 111 Transaminase Activities of Serum and Body Fluids, the Clinical Significance of Alterations in (Wroblew-ski), 1, 314... 

The combination of MALDI-TOF MS and capillary LC/MS/MS was recently described for the identification of disease state markers in human urine. In this study, urine proteins obtained from emphysema patients were separated on 2-D gels and selected spots were digested with trypsin and analyzed by MALDI-TOF. A database search using Protein Prospector identified a potential biomarker for emphysema as human alpha-1-antitrypsin (AlAT). The corresponding MALDI spectrum contained nine out of 18 peptides with masses that match the expected tryptic digest fragments for AlAT. 

Heine, G., Raida, M., Forssmann, W. G. (1997). Mapping of peptides and protein fragments in human urine using liquid chromatography-mass spectrometry. Journal of Chromatography. A, 776, 117-124. 

W3. Wittke, S., Fliser, D., Haubitz, M., et al.. Determination of peptides and proteins in human urine with capillary electrophoresis-mass spectrometry, a suitable tool for the establishment of new diagnostic markers. J. Chromatog. A. 1013, 173-181 (2003). 

In support of its role as an intermediate in purine metabolism, adenylosuccinic acid has been isolated from mammalian liver (164) and from Penidllium chrysogenum (166). The free base, adeninosuccinic acid [6-(succinoamino) purine], was identified in human urine (166) and isolated from Neurospora mutants (167, 168). Also, the ribonucleoside derivative of adeninosuccinic acid (adeno lsuccinic acid) has been found in human cerebrospinal fluid (169) and in a Neurospora mutant (168). Another adenylosuccinate compound contained sulfate in a ribos fi -phosphosulfate linkage as well as a peptide residue, but its significance is not known (160). 

A few indole derivatives are phytohormones. The most important of them is /3-indolylacetic acid, indole-3-acetic acid or, abbreviated, lAA (Fig. 160). It was detected in 1934 by Kogl in human urine, then in microorganisms, and, finally, also in higher plants. lAA occurs in plants either free or bound, e.g. esterifield to glucose or in peptide linkage with aspartic acid and glutamic acid. 

The quantification of kinins in human tissues or body fluids has been limited due to the inherent difficulties in accurately measuring the concentration of ephemeral peptides. Today HPLC-based and RIA/capture-ELA measurements are established to determine kinins in human plasma, liquor or mine. Serine protease inhibitors need to be added to prevent rapid degradation of the kinins in vitro during sample preparation. Kinins and their degradation products have been studied in various biological milieus such as plasma/ serum, urine, joint fluids, kidney, lung and skeletal muscle [2]. Under normal conditions, the concentration of kinins in these compartments is extremely low for... 

Urokinase Urokinase is an enzyme that is extracted from human urine or kidney cells [46-55], which directly cleaves specific peptide bonds, in particular the Arg-560-Val-561 bond in the plasminogen molecule, thus transforming it into plasmin. It is used for the same indications as streptokinase. Synonyms of this drug are abbokinase and others. 

GnRH is also used (in both human and veterinary medicine) to improve conception rates by enhancing basal hypothalamic-pituitary function. The preparations utilized clinically are manufactured by direct chemical synthesis and are usually administered by s.c. injection or, sometimes, by i.v. injection. Occasionally it has also been administered intranasally. Frequent injection is often required, particularly if administration is via the i.v. route, as the peptide s plasma half-life is of the order of a few minutes (it is hydrolysed in the plasma and excreted in the urine). 

CRH is administered intravenously. The first-phase half-lives of human and sheep CRH are 9 minutes and 18 minutes, respectively. The peptide is metabolized in various tissues, and less than 1% is excreted in the urine. 

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