Lesion of the lateral entorhinal cortex amplifies odor-induced expression of c-fos, junB, and zif 268 mRNA in rat brain.
Paradoxical facilitation of olfactory learning following entorhinal cortex (EC) lesion has been described, which may result from widespread functional alterations taking place within the olfactory system. To test this hypothesis, expression of the immediate early genes c-fos, junB, and zif 268 was studied in response to an olfactory stimulation in several brain areas in control and in EC-lesioned rats. Olfactory stimulation in control rats induced the expression of the three genes in the granular/mitral and glomerular layers of the olfactory bulb, as well as c-fos and junB expression in the piriform cortex. However EC lesion was devoid of effects in nonstimulated animals; it significantly amplified the odor-induced expression of the three genes in these areas, as well as in the amygdala, hippocampus, and parietal-temporal cortices. The data suggest that EC lesion modifies the neural processing of odor by suppressing an inhibitory influence on brain areas connected to this cortex.
Bernabeu
Ramón
R
Laboratoire de Neurosciences Comportementales et Cognitives, UMR 7521, Université Louis Pasteur/CNRS, Strasbourg 67000, France.
Thiriet
Nathalie
N
Zwiller
Jean
J
Di Scala
Georges
G
D000679:Amygdala / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001345:Autoradiography; D001923:Brain Chemistry / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D051766:Early Growth Response Protein 1 / Q000235:genetics*; D018728:Entorhinal Cortex / Q000187:drug effects / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D016762:Genes, fos / Q000235:genetics*; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology; D017403:In Situ Hybridization; D066298:In Vitro Techniques; D008297:Male; D009812:Odorants; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D020318:Rats, Long-Evans
D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D016755:Proto-Oncogene Proteins c-jun; D012333:RNA, Messenger