Photopic electroretinograms of mGluR6-deficient mice.
OBJECTIVE
To study the properties of the photopic electroretinograms (ERGs) of the metabotropic glutamate receptor subtype 6 (mGluR6)-deficient mice and to investigate the contribution of cone ON-and OFF-pathways to the mouse photopic ERGs.


METHODS
Photopic ERGs were recorded from mGluR6-deficient and wild-type mice. Photopic ERGs were also recorded after an intravitreous injection of cis-2,3 piperidine dicarboxylic acid (PDA) to block the transmission of signals from the photoreceptors to the OFF-bipolar cells, horizontal cells, and other inner retinal neurons.


RESULTS
The amplitude of the b-wave of the photopic ERG was severely reduced in mGluR6-deficient mice, but a small, slow, positive component was seen after the a-wave. Intravitreous injection of PDA eliminated this positive component.


CONCLUSIONS
The mGluR6-deficient mouse is a useful animal model to study the contribution of the ON-and OFF-pathways to the mouse ERG.
Koyasu
Toshiyuki
T
Department of Ophthalmology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
Kondo
Mineo
M
Miyata
Kentaro
K
Ueno
Shinji
S
Miyata
Takaki
T
Nishizawa
Yuji
Y
Terasaki
Hiroko
H
D000818:Animals; D004596:Electroretinography; D018691:Excitatory Amino Acid Antagonists / Q000633:toxicity; D005838:Genotype; D007267:Injections; D008027:Light; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D020419:Photoreceptor Cells, Vertebrate / Q000187:drug effects / Q000502:physiology*; D010875:Pipecolic Acids / Q000633:toxicity; D016133:Polymerase Chain Reaction; D018094:Receptors, Metabotropic Glutamate / Q000172:deficiency / Q000502:physiology*; D051245:Retinal Bipolar Cells / Q000187:drug effects / Q000502:physiology; D051248:Retinal Horizontal Cells / Q000187:drug effects / Q000502:physiology; D014795:Visual Pathways / Q000187:drug effects / Q000502:physiology; D014822:Vitreous Body
D018691:Excitatory Amino Acid Antagonists; D010875:Pipecolic Acids; D018094:Receptors, Metabotropic Glutamate; C113897:metabotropic glutamate receptor 6; C029262:2,3-piperidinedicarboxylic acid