EXPRESSION OF HEPARIN-BINDING EPIDERMAL GROWTH FACTOR-LIKE GROWTH-FACTOR IN RAT-BRAIN

According to a recent report, messenger RNA coding for a member of the epidermal growth factor (EGF) family, heparin-binding EGF-like growth factor (HB-EGF), is expressed in the central nervous system (CNS). To obtain information about the role of HB-EGF in the brain, we carried out Northern analysis, in situ hybridization, and immunohistochemical studies evaluating the distribution and amounts of the growth factor u sing cDNA HB-EGF probes and an antibody raised against synthetic HB-EG F propeptide. Northern analysis revealed transcripts for HB-EGF in all regions of normal rat brain. Immunohistochemically, HB-EGF was demons trated extensively in neurons at levels varying according to location. HB-EGF mRNA also was detected in neurons, suggesting that the growth factor is produced in these cells. HB-EGF mRNA and immunoreactivity we re also demonstrated in interfascicular oligodendrocytes. These findin gs suggest that HB-EGF is a physiologic ligand for brain EGF receptors , and is likely to be important in neural function. (C) 1998 Elsevier Science B.V.