title: Social isolation stress down-regulates cortical early growth response 1 (Egr-1) expression in mice.
abstract: Social isolation stress induces behavioral disturbances such as aggression, cognitive impairments, and deficits in prepulse inhibition in mice. Social isolation mice have, therefore, been studied as an animal model of neuropsychiatric disorders such as schizophrenia. Recently, the decrease in early growth response (Egr) gene expression levels were reported in the post-mortem brains of schizophrenia patients. In this study, we investigate the effects of social isolation stress on the expression levels of Egr mRNA and protein in the frontal cortex. Social isolation stress exposure significantly down-regulated the expression of Egr-1 protein and Egr-1 gene transcript in nucleus of cortical neurons in a manner dependent on a social isolation period. This stress had no effect on the expression level of Egr-1 in the striatum or the expression levels of other Egr family members (Egr-2, -3, and -4) in the frontal cortex. These results suggest that the decrease in Egr-1 expression in the frontal cortex may be involved in social isolation stress-induced behavioral abnormalities.
authors.affiliation: Division of Medicinal Pharmacology, Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan. mkinzo@inm.u-toyama.ac.jp
authors.forename: Kinzo
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Kazuya
authors.initials: K
authors.lastname: Ono
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Ouchi
authors.forename: Ryohei
authors.initials: R
authors.lastname: Tsushima
authors.forename: Yukihisa
authors.initials: Y
authors.lastname: Murakami
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000235:genetics; D051766:Early Growth Response Protein 1 / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics; D005625:Frontal Lobe / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D019965:Neurocognitive Disorders / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D012934:Social Isolation / Q000523:psychology; D013315:Stress, Psychological / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology
chemical_list: D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse