title: Rubidium content in autopsy liver tissue samples from Greenlandic Inuit and Danes measured by X-ray fluorescence spectrometry.
abstract: BACKGROUND
  The biological function of rubidium (Rb) is unknown, but this alkali metal probably has a normal biologic role.
  
  
  OBJECTIVE
  To measure the content of Rb in liver tissue samples from Greenlandic Inuit using X-ray fluorescence spectrometry, and compare the results with those obtained in liver samples from ethnic Danes.
  
  
  METHODS
  Observational, descriptive survey on environmental pathology.
  
  
  METHODS
  The setting was related to forensic medicine and hospitalised care in Nuuk, Ilulissat and Copenhagen. Normal liver tissue was obtained at autopsy from 50 Greenlandic Inuit (27 men) with a median age of 61 years (range 23-83) and from 42 Danes (31 men) with a median age of 38 years (range 16-83).
  
  
  RESULTS
  Liver Rb content in Inuit was not significantly different compared with Danes. There was no significant gender difference in liver Rb content either in Inuit or in Danes. The content of Rb given as median (5-95 percentile) was 0.1837mmol/kg dry liver (0.1041-0.3147) in Inuit, and 0.1965mmol/kg dry liver (0.0799-0.2815) in Danes (p=0.6). There was an inverse correlation between liver Rb content and age in Inuit (r(s)=-0.45, p=0.002) but not in Danes. Median hepatic Rb index (Rb content in micromol/kg dry weight divided by age in years) in Inuit was 3.05 and in Danes 4.21 (p=0.02). The correlations between liver Rb and liver potassium content were: Inuit r(s)=0.28, p=0.07; Danes r(s)=0.25, p=0.08; combined series r(s)=0.34, p=0.01.
  
  
  CONCLUSIONS
  Inuit have liver Rb levels, which are quite similar to the levels found in Danes. In Inuit, liver Rb content appears to decrease with age.
authors.affiliation: Department of Medicine B 2142, University of Copenhagen, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen Ø, Denmark. milman@rh.dk
authors.forename: Nils
authors.initials: N
authors.lastname: Milman
authors.forename: Jens
authors.initials: J
authors.lastname: Laursen
authors.forename: Keld-Erik
authors.initials: KE
authors.lastname: Byg
authors.forename: Henning S
authors.initials: HS
authors.lastname: Pedersen
authors.forename: Gert
authors.initials: G
authors.lastname: Mulvad
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D003718:Denmark / Q000453:epidemiology; D005006:Ethnicity; D006116:Greenland / Q000453:epidemiology; D006801:Humans; D004930:Inuit; D008099:Liver / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012413:Rubidium / Q000378:metabolism*; D013052:Spectrometry, X-Ray Emission; D013997:Time Factors
chemical_list: D012413:Rubidium