Animal Production Program

  01C55 C57BL/6N
(C Black 6, C57 Black subline 6, B6)

Origin: To N 1951 from Jax at F32. See C57BL/KaLwN; strains 6 and 10 separated prior to 1937. To Jax in 1948 from Hall.
Genetics:

a, B, C
Intense black
Genes:

Car-2a, Ce-2a, Cs-1g, Es-1a, Es-3a, Es-10a, Gpd-1a, Gpi-1b, Gusb, Hbaa, Hbbs, Idh-1a, Lvb, Mod-1b, Mup-1b, Pep-3a, Pgm-1a, Trfb
Hc1, H-2Db, H-2Kb, Lyb-2b, Lyt-1b, Lyt-2b, Lyt-3b, Thy-1b, Tlab.

   
Diseases
    Neoplastic (Spontaneous):
 
  • Very low incidence of mammary tumors. (274)
   
    Neoplastic (Induced):
 
  • More than 75% developed pulmonary metastases within 50 days of amputation of legs with autochthonous 3-methylcholanthrene-induced sarcomas providing a useful model for studies of metastases and evaluation of cancer therapy in a minimal residual disease setting. (790)
  • N-butylnitrosourea induced leukemia in 91% of C57BL/6J mice; thymic lymphoblastic, 0-alloantigen-positive (T cell) leukemia predominated with a few cases of non-thymic or stem cell leukemia. Thymectomy reduced the incidence to 64%. (659)
  • 3-Methylcholanthrene induced brain tumors in 60% of males. (404)
  • Dietary acetylaminofluorene or chlordane induced elevated 0-fetoprotein levels and malignant hepatic lesions. (049)
  • In comparison with other inbred strains, C57BL/6 is resistant to Gross, Tennant, and Friend B viruses. (370)
   
    Non-Neoplastic (Spontaneous):
 
  • No dystrophic cardiac calcinosis detected in either sex. (160)
  • Intestinal volvulus in a small percentage. (140)
   
    Non-Neoplastic (Induced):
 
  • Incidence of cortisone-induced cleft palate much higher on one commercial diet than on another. (464)
  • Relatively resistant to ectromelia. (632)
  • Susceptible to infection with Leishmania tropica, but no clinical signs of disease. (063)
  • Benzo(a)pyrene administration at day 7 or 10 of gestation caused in utero toxicity and teratogenicity more in C57BL/6 thant in Akr mice. Allelic differences at the Ah locus in the fetus were correlated with dysmorphogenesis. (664)
   
Other Characteristics
    Immunologic:
 
  • BCG pretreatment accelerated the recovery of granuloctye counts after cyclophosphamide-induced leukopenia. (386)
  • Delayed hypersensitivity to methylated serum albumin was enhanced by cycloposphamide in young, but not old mice. (469)
  • High interferon production after induction with Newcastle disease virus or mammary tumor virus. (131)
  • Responsive to pertussis HSF. (778,500)
  • Two Lyt differentiated thymocyte populations were detected: one with Lyt-1+ and one with Lyt 123+. (445)
   
    Biochemical:
 
  • Aryl hydrocarbon hydroxylase is inducible by 3-methylcholanthrene and other polycyclic hydrocarbons. The “responsive” Ahb allele is present. (404,403)
  • Morphine increased 3-methoxytyramine and cyclic AMP levels in striatum. (561)
  • Liver alcohol dehydrogenase and aldehyde dehydrogenase activities 30% and 300% greater, respectively, than those of DBA/2. (299)
 
    Behavioral:
 
  • High preference for alcohol and for morphine presented in a saccharin vehicle. (794)
 
    Misc:
 
  • Survival time ws significantly shortened by the intraperitoneal, but not oral administration of benzo(a)pyrene. (737)
  • 3-Methylcholanthrene was more toxic to C57BL/6N primordial oocytes than to DBA/2N oocytes. (447)
  • Resistant to audiogenic seizures at all ages, but susceptibility enhanced by treatment with excess thyroxine. (647,646)
  • Less sensitive to analgesic action of morphine than DBA/2 and locomotor response is higher. (561)
  • Resistant to toxic effects of chloroform. (127,097)