Mouse Genome Informatics
hm
    Cyb5r4tm1Hfb/Cyb5r4tm1Hfb
involves: 129S4/SvJae * BALB/cAnN
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
       

Immunohistochemical and ultrastructural assessment of insulin- and glucagon-producing cells in Cyb5r4tm1Hfb/Cyb5r4tm1Hfb mice

homeostasis/metabolism
• early defect in glucose stimulated insulin secretion but not in glucose sensing pathway
• normal glucose levels at 4 weeks of age in a fed state
• by 7 weeks of age blood glucose is 3X normal in the fed state or after overnight fasting
• insulin levels 40% of normal at 4 weeks of age
• insulin levels 25% normal at 7 weeks of age and barely detectable after fasting
• impaired tolerance for glucose given ip at 4 weeks of age
• insulin tolerance is normal but with a slight increase in insulin sensitivity

endocrine/exocrine glands
• decreased cytoplasm to nuclear ratio in islet cells
• no inflammatory cells or necrotic beta cells
• cell distribution pattern normal at 4 weeks of age
• beta cell numbers decreased at 7 weeks of age
• at 21 weeks a very small number of beta cells are left
• increased size and number of mitochondria
• early defect in glucose stimulated insulin secretion but not in glucose sensing pathway

adipose tissue
• decreased adipose tissue mass

behavior/neurological
• increased food intake

growth/size/body
• decreased adipose tissue mass

Mouse Models of Human Disease
OMIM IDRef(s)
Diabetes Mellitus, Noninsulin-Dependent; NIDDM 125853 J:91486