A naturally occurring mouse model of X-linked congenital stationary night blindness.
OBJECTIVE
To describe a naturally occurring X-linked recessive mutation, no b-wave (nob), that compromises visual transmission between photoreceptors and second-order neurons in mice.


METHODS
Affected mice were identified by recording the light-evoked response of the retina, the electroretinogram (ERG). To evaluate visual transmission, cortical potentials were recorded with a scalp electrode. The inheritance pattern for nob was defined by breeding nob animals with normal mice. Retinal histologic analysis was performed by light microscopy.


RESULTS
Although the photoreceptor-mediated ERG component (a-wave) was normal in nob mice, the major response component reflecting postreceptoral neuronal activity (b-wave) was missing. Visually-driven cortical activity was also abnormal in nob animals. At the light microscopic level, the nob retina appeared to have a normal cytoarchitecture.


CONCLUSIONS
These findings suggest that the nob defect interferes with the transmission of visual information through the retina and that these mice are a useful model for the study of outer retinal synaptic function. In addition, this mutant mouse seems to provide an animal model for the complete form of congenital stationary night blindness, a human disorder in which patients have a profound loss of rod-mediated visual sensitivity.
Pardue
M T
MT
Research Service, Hines VA Hospital, Illinois 60141, USA.
McCall
M A
MA
LaVail
M M
MM
Gregg
R G
RG
Peachey
N S
NS
D000818:Animals; D003623:Dark Adaptation; D004195:Disease Models, Animal; D004596:Electroretinography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D008040:Genetic Linkage; D008027:Light; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008817:Mice, Mutant Strains; D009154:Mutation; D009474:Neurons / Q000473:pathology / Q000502:physiology; D009755:Night Blindness / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D010375:Pedigree; D017956:Photoreceptor Cells, Invertebrate / Q000473:pathology / Q000503:physiopathology; D014785:Vision, Ocular; D014960:X Chromosome / Q000235:genetics*