title: Two-dimensional LC-MS/MS in detection of peptides in hypothalamus of the rat subjected to hypoxic stress.
abstract: A capillary 2-D LC method coupled with IT MS has been used for separation and identification of peptides in rat hypothalamus. Animals of two different age groups (8 and 50 wk) were exposed to two different rates of CO(2 )in inhaled air to investigate the influence of different hypoxia/hypercapnia levels and their stress-related factor on the peptide excretion. Peptide compounds were fractionated (strong cation exchange chromatography), trapped, and separated (RP chromatography), and MS/MS mass spectra were used for identification. About 107 peptide compounds were identified and 88 of them were semiquantified. Among the characterized peptides, there were fragments from proteins such as proenkephalin A, proSAAS, prosomatostatin, prooxytocin, vasopressin, etc. Explorative principal component analysis (PCA) combined with hypothesis testing was applied to the obtained data to investigate the impact of age and hypoxic stress factors on the peptide pattern. Twenty-six peptides revealed significant differences in concentrations between the animal groups influenced by age and influx rate.
authors.affiliation: Department of Chemistry, University of Oslo, Blindern, Norway. albenam@kjemi.uio.no
authors.forename: Albena
authors.initials: A
authors.lastname: Mihailova
authors.forename: Bartosz
authors.initials: B
authors.lastname: Karaszewski
authors.forename: Ellen Mosleth
authors.initials: EM
authors.lastname: Faergestad
authors.forename: Roman
authors.initials: R
authors.lastname: Hauser
authors.forename: Walenty M
authors.initials: WM
authors.lastname: Nyka
authors.forename: Elsa
authors.initials: E
authors.lastname: Lundanes
authors.forename: Tyge
authors.initials: T
authors.lastname: Greibrokk
mesh_terms: D000367:Age Factors; D000818:Animals; D002245:Carbon Dioxide / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods; D006935:Hypercapnia / Q000378:metabolism; D007031:Hypothalamus / Q000737:chemistry* / Q000378:metabolism*; D000860:Hypoxia / Q000378:metabolism*; D008297:Male; D010455:Peptides / Q000032:analysis*; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013997:Time Factors
chemical_list: D010455:Peptides; D002245:Carbon Dioxide