Ciliary neurotrophic factor induces expression of the IGF type I receptor and FGF receptor 1 mRNAs in adult rat brain oligodendrocytes

✍ Scribed by Fengjun Jiang; Steven W. Levison; Teresa L. Wood

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 744 KB
• Volume: 57
• Category: Article
• ISSN: 0360-4012
• DOI: 10.1002/(sici)1097-4547(19990815)57:4<447::aid-jnr4>3.0.co;2-b

✦ Synopsis

Ciliary neurotrophic factor (CNTF) is produced and released in response to injury in the central nervous system (CNS). While CNTF initially was characterized as a trophic factor for neurons, more recent evidence supports roles for this factor in survival, proliferation, and maturation of oligodendrocyte lineage cells. Evidence is emerging to support the hypothesis that CNTF's actions may include enhancing other growth and trophic factors. Here we tested the hypothesis that CNTF can induce expression of receptors on oligodendrocytes for factors that are known to promote their generation, maturation, and survival. Specifically, we used an in vivo paradigm to test whether CNTF, when injected stereotactically into forebrain white matter of adult rats, could induce mRNA expression for the insulin-like growth factor (IGF) type I receptor (IGF-IR), fibroblast growth factor (FGF) receptor (FGFR)-1, FGFR3, and plateletderived growth factor (PDGF) receptor-alpha (PDGFR␣). We determined that CNTF injection increased expression of IGF-IR and FGFR1 mRNAs in adult white matter to 200-250% of control levels. Cellular analysis indicated that these receptor mRNAs were induced in interfascicular oligodendrocytes. In contrast, CNTF had no effect on levels of FGFR3 and PDGFR␣ mRNAs. These results suggest that CNTF enhances the sensitivity of oligodendrocytes to other mitogens and trophic factors via induction of their receptors.