Phenotypes associated with this allele
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Bdnftm1Tbn mutation
(0 available);
any
Bdnf mutation
(39 available)
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nervous system
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• abnormal sympathetic innervation; adrenergic hypoinnervation in the dorsal skin
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• abnormal sympathetic innervation; adrenergic hypoinnervation in the dorsal skin
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• reduction in the number of dermal adrenergic fibers
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integument
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• reduced numbers of proliferating epidermal keratinocytes
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Bdnftm1Tbn mutation
(0 available);
any
Bdnf mutation
(39 available)
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mortality/aging
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• homozygotes usually die between 2 and 4 weeks of age
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endocrine/exocrine glands
growth/size/body
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• at >P3, homozygotes display a 75% reduction in body weight relative to wild-type mice
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• at P3 or later, homozygotes are growth retarded relative to wild-type littermates
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behavior/neurological
nervous system
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• type II afferent fibers lacking at birth and first post natal week in the medial and apical turns of the cochlea but they are present in the basal turn
• at age 19 days the pattern is reversed
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• homozygotes exhibit a loss of neurons in the dorsal root ganglia
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• homozygotes exhibit a loss of neurons in the dorsal root ganglia
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• frequency distributions of posttetanic synaptic enhancements indicate that in homozygotes most potentiations are close to 100% vs >150% in wild-type mice
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• after tetanic stimulation, homozygotes exhibit significantly reduced mean field EPSP slopes relative to wild-type mice, even when only successful LTPs are included
• in contrast, paired pulse facilitation (ratio of second EPSP slope to first EPSP slope) is unaffected
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• homozygotes show almost no LTP in the CA1 region of the hippocampus until P16 (only 1 successful LTP in 19 slices; 5%)
• from P17 to P28, the % of successful LTPs rises to 32.6%, but the magnitude is significantly smaller than in wild-type mice and declines slowly over time
• notably, general hippocampus anatomy and hippocampal pyramidal neuron morphology and pharmacology appear to be normal
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digestive/alimentary system
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• generally hypotrophic
• mucosal layers of ileum and duodenum are normal
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hearing/vestibular/ear
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• type II afferent fibers lacking at birth and first post natal week in the medial and apical turns of the cochlea but they are present in the basal turn
• at age 19 days the pattern is reversed
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integument
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• after 22 days, most hair follicles in later stages of regression (catagen) while controls are at the end of catagen or in the resting phase (telogen)
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cellular
Allelic
Composition |
Bdnftm1Tbn/Bdnf+
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Genetic
Background |
involves: 129S4/SvJae * NMRI |
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Bdnftm1Tbn mutation
(0 available);
any
Bdnf mutation
(39 available)
|
|
|
nervous system
|
|
• frequency distributions of posttetanic synaptic enhancements indicate that in heterozygotes most potentiations are close to 100% vs >150% in wild-type mice
• after P16, heterozygotes display almost no differences in posttetanic synaptic strengthening relative to homozygotes
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• after tetanic stimulation, heterozygotes exhibit a similar reduction in mean field EPSP slopes to that observed in homozygotes
• as in homozygotes, paired pulse facilitation (ratio of second EPSP slope to first EPSP slope) is unaffected
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• heterozygotes display a similar reduction in LTP magnitude and % of successful LTPs in the CA1 region of the hippocampus to that observed in homozygotes
• again, the magnitude of potentiation is significantly smaller than in wild-type mice and declines slowly over time
• in contrast to homozygotes, heterozygotes are viable and display normal dorsal root ganglia and no balance or coordination deficits
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Analysis Tools