title: [Lactase and its gene regulation in BALB/c mice at different ages].
abstract: OBJECTIVE
  In order to clarify the trend of change in lactase and its gene regulation pattern, the authors determined the lactase activities and mRNA levels in BALB/c mice at different ages.
  
  
  METHODS
  The lactase activities and mRNA levels of the 3-, 5-, 7-, 9- week old mice were determined by the modified method of Dahlqvist and in situ hybridization respectively.
  
  
  RESULTS
  The 3 wk old mice had the highest lactase activities, to the contrary, the 9 wk old mice had the lowest lactase activities. Meanwhile, the lactase mRNA levels displayed no diversities.
  
  
  CONCLUSIONS
  The mice had higher lactase activities before weaning, but significantly very low activities after weaning. These findings indicate that BALB/c mice have the same adult-type hypolactasia as human. No statistically significant difference in lactase mRNA levels between the 4 age-groups implies that lactase gene is regulated at the translational and/or post-translational levels, but not at the transcriptional level.
authors.affiliation: Department of Nutrition and Food Hygiene, West China School of Public Health, Sichuan University, Chengdu 610041, China.
authors.forename: Wei
authors.initials: W
authors.lastname: He
authors.forename: Bin
authors.initials: B
authors.lastname: Lü
authors.forename: Chengyu
authors.initials: C
authors.lastname: Huang
mesh_terms: D000367:Age Factors; D000818:Animals; D005260:Female; D005786:Gene Expression Regulation; D043322:Lactase / Q000235:genetics / Q000378:metabolism*; D007787:Lactose Intolerance / Q000235:genetics*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D043322:Lactase