title: Measurement of manganese content in various organs in rats with or without glucose stimulation.
abstract: Our purpose in this study was to assess the manganese (Mn) content in various organs in rats with or without glucose stimulation in vivo and in vitro by using magnetic resonance imaging (MRI) and polarized Zeeman atomic absorption spectrophotometry (PZAAS), respectively. MRI studies were performed in 12 rats using a 1.5-T MRI system. The rats were injected intravenously with saline (6 ml/kg) (saline-stimulated group, n = 6) or glucose (2.34 g/kg) (glucose-stimulated group, n = 6). Ten minutes after saline or glucose administration, MnCl₂ (0.02 mmol/kg) was injected intravenously, followed by 6 MRI studies at 8-min intervals. After the last MRI study, rats were killed, and the Mn concentrations in various organs were measured using PZAAS. There was a discrepancy between in vivo and in vitro measurements, which appeared to be due to the partial volume effect and/or the contribution of extracellular Mn. The Mn concentration in the pancreas, normalized to that in the liver in the glucose-stimulated group, increased significantly compared to that in the saline-stimulated group, suggesting that the influx of Mn into β cells in the pancreas increased in response to glucose stimulation. This study suggested that the measurement of the change in the Mn concentration due to glucose stimulation using PZAAS was effective for evaluating β-cell function in the pancreas.
authors.affiliation: Division of Medical Technology and Science, Department of Medical Physics and Engineering, Faculty of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Nagata
authors.forename: Toshio
authors.initials: T
authors.lastname: Kagawa
authors.forename: Daichi
authors.initials: D
authors.lastname: Koutou
authors.forename: Taro
authors.initials: T
authors.lastname: Matsushita
authors.forename: Youichi
authors.initials: Y
authors.lastname: Yamazaki
authors.forename: Kenya
authors.initials: K
authors.lastname: Murase
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D005947:Glucose / Q000494:pharmacology*; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008345:Manganese / Q000032:analysis* / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D013054:Spectrophotometry, Atomic; D014018:Tissue Distribution / Q000187:drug effects
chemical_list: D008345:Manganese; D005947:Glucose
references.citation: Am J Physiol. 1999 Mar;276(3):E512-8
references.pmid: 10070018
references.citation: Am J Physiol Endocrinol Metab. 2009 Mar;296(3):E573-8
references.pmid: 19116376
references.citation: Acta Radiol. 1997 Jul;38(4 Pt 2):700-7
references.pmid: 9245965
references.citation: Cell Transplant. 2006;15(2):195-203
references.pmid: 16719054
references.citation: Magn Reson Med. 1997 Sep;38(3):378-88
references.pmid: 9339438
references.citation: NMR Biomed. 2004 Dec;17(8):532-43
references.pmid: 15617052
references.citation: Magn Reson Med. 2002 Nov;48(5):852-9
references.pmid: 12418000
references.citation: Neuroimage. 2004 Jul;22(3):1046-59
references.pmid: 15219577
references.citation: Science. 1972 Apr 21;176(4032):308-9
references.pmid: 5019787
references.citation: Circ Res. 1980 Nov;47(5):721-7
references.pmid: 6774832
references.citation: Nat Neurosci. 2005 Jul;8(7):961-8
references.pmid: 15924136
references.citation: Eur J Radiol. 2009 May;70(2):254-7
references.pmid: 19261414