Decreased expression of extracellular matrix proteins and trophic factors in the amygdala complex of depressed mice after chronic immobilization stress

• Published in: BMC neuroscience Vol. 13; no. 1; p. 58
• Main Authors: Jung, Soonwoong, Lee, Younghyurk, Kim, Gyeongwha, Son, Hyeonwi, Lee, Dong Hoon, Roh, Gu Seob, Kang, Sang Soo, Cho, Gyeong Jae, Choi, Wan Sung, Kim, Hyun Joon
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 06.06.2012; BioMed Central; BMC
• Subjects: Amygdala; Amygdala (Brain); Amygdala - metabolism; Analysis; Analysis of Variance; Animal models; Animals; Anxiety; Brain; Brain research; Conditioning, Operant - physiology; Depression; Depression - etiology; Depression - pathology; Depression, Mental; Disease Models, Animal; Down-Regulation - physiology; Emotional behavior; Extracellular matrix; Extracellular Matrix Proteins - genetics; Extracellular Matrix Proteins - metabolism; Fibromodulin; Food Preferences - physiology; Gene expression; Gene Expression Profiling; Genes; Genetic aspects; Immobilization; Insulin-Like Growth Factor Binding Protein 2 - metabolism; Insulin-like growth factor II; Insulin-Like Growth Factor II - genetics; Insulin-Like Growth Factor II - metabolism; Insulin-like growth factor-binding protein 2; Intercellular Signaling Peptides and Proteins - metabolism; Male; Mice; Mice, Inbred C57BL; Mice, Inbred ICR; Nerve Growth Factors - genetics; Nerve Growth Factors - metabolism; Nervous system; Neurotrophic factors; Oligonucleotide Array Sequence Analysis; Osteoglycin; Physiological aspects; Protein binding; Proteins; Proteoglycans - metabolism; Restraint, Physical - adverse effects; RNA, Messenger - metabolism; Stress; Studies; Trophic factors; South Korea
• ISSN: 1471-2202; 1471-2202
• DOI: 10.1186/1471-2202-13-58

The amygdala plays an essential role in controlling emotional behaviors and has numerous connections to other brain regions. The functional role of the amygdala has been highlighted by various studies of stress-induced behavioral changes. Here we investigated gene expression changes in the amygdala in the chronic immobilization stress (CIS)-induced depression model. Eight genes were decreased in the amygdala of CIS mice, including genes for neurotrophic factors and extracellular matrix proteins. Among these, osteoglycin, fibromodulin, insulin-like growth factor 2 (Igf2), and insulin-like growth factor binding protein 2 (Igfbp2) were further analyzed for histological expression changes. The expression of osteoglycin and fibromodulin simultaneously decreased in the medial, basolateral, and central amygdala regions. However, Igf2 and Igfbp2 decreased specifically in the central nucleus of the amygdala. Interestingly, this decrease was found only in the amygdala of mice showing higher immobility, but not in mice displaying lower immobility, although the CIS regimen was the same for both groups. These results suggest that the responsiveness of the amygdala may play a role in the sensitivity of CIS-induced behavioral changes in mice.