Deficiency of Vlgr1 resulted in deafness and susceptibility to audiogenic seizures while the degree of hearing impairment was not correlated with seizure severity in C57BL/6- and 129-backcrossed lines of Vlgr1 knockout mice.
Vlgr1 (very large G-protein coupled receptor 1) knockout mice against hybrid backgrounds of the 129/Ola and C57BL/6 mouse strains show hearing deficit and high susceptibility to audiogenic seizures. The present study examined how hearing impairment and susceptibility to audiogenic seizures in Vlgr1-deficient mice change according to the genetic background of 129 and C57BL/6 mouse strains, which are popular strains for genetic studies. C57BL/6 mice have normal hearing ability during adolescence and are resistant to audiogenic seizures, and the 129S1/SvImJ substrain does not have a severe hearing deficit or convulsions as a result of audiogenic seizures; therefore, these strains were chosen for the present backcross study. C57BL/6-backcrossed Vlgr1 knockout mice and 129 (129S1/SvImJ)-backcrossed Vlgr1 knockout mice were established and their phenotypes investigated. Vlgr1 knockout mice showed hearing loss and high susceptibility to audiogenic seizures regardless of their genetic backgrounds. 129-backcrossed Vlgr1 knockout mice exhibited 10-20dB more severe hearing loss than C57BL/6-backcrossed Vlgr1 knockout mice. In general, 129-backcrossed Vlgr1 knockout mice showed a higher incidence of wild running than C57BL/6-backcrossed Vlgr1 knockout mice, and this incidence became smaller as they matured. However, C57BL/6-backcrossed Vlgr1 knockout mice showed a significantly higher mortality rate as a result of auditory stimulation 3 weeks postnatally than 129-backcrossed mice.
Yagi
Hideshi
H
Division of Cell Biology and Neuroscience, Department of Morphological and Physiological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan. yagi@u-fukui.ac.jp
Noguchi
Yoshihiro
Y
Kitamura
Ken
K
Sato
Makoto
M
D000367:Age Factors; D000818:Animals; D003638:Deafness / Q000235:genetics; D020195:Epilepsy, Reflex / Q000235:genetics*; D016057:Evoked Potentials, Auditory, Brain Stem; D020022:Genetic Predisposition to Disease; D034381:Hearing Loss / Q000235:genetics*; D007178:Inbreeding; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009154:Mutation; D043562:Receptors, G-Protein-Coupled / Q000235:genetics*; D012640:Seizures / Q000235:genetics*
D043562:Receptors, G-Protein-Coupled; C485949:Adgrv1 protein, mouse