Fos imaging reveals that lesions of the anterior thalamic nuclei produce widespread limbic hypoactivity in rats.
Activity of the immediate early gene c-fos was compared in rats with neurotoxic lesions of the anterior thalamic nuclei and in surgical controls. Fos levels were measured after rats had been placed in a novel room and allowed to run up and down preselected arms of a radial maze. An additional control group showed that in normal rats, this exposure to a novel room leads to a Fos increase in a number of structures, including the anterior thalamic nuclei and hippocampus. In contrast, rats with anterior thalamic lesions were found to have significantly less Fos-positive cells in an array of sites, including the hippocampus (dorsal and ventral), retrosplenial cortex, anterior cingulate cortex, and prelimbic cortex. These results show that anterior thalamic lesions disrupt multiple limbic brain regions, producing hypoactivity in sites associated in rats with spatial memory. Because many of the same sites are implicated in memory processes in humans (e.g., the hippocampus and retrosplenial cortex), this hypoactivity might contribute to diencephalic amnesia.
Jenkins
Trisha A
TA
School of Psychology, Cardiff University, Cardiff CF10 3YG, United Kingdom.
Dias
Rebecca
R
Amin
Eman
E
Brown
Malcolm W
MW
Aggleton
John P
JP
D000818:Animals; D020643:Anterior Thalamic Nuclei / Q000737:chemistry / Q000473:pathology*; D001522:Behavior, Animal; D016923:Cell Death; D002540:Cerebral Cortex / Q000737:chemistry; D006179:Gyrus Cinguli / Q000737:chemistry; D006624:Hippocampus / Q000737:chemistry; D007150:Immunohistochemistry; D008032:Limbic System / Q000737:chemistry / Q000503:physiopathology*; D008297:Male; D018782:Maze Learning; D008568:Memory; D020258:Neurotoxicity Syndromes / Q000473:pathology / Q000503:physiopathology* / Q000523:psychology; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis* / Q000276:immunology; D051381:Rats
D016760:Proto-Oncogene Proteins c-fos