title: Increased expression of neurotrophin 4 following focal cerebral ischemia in adult rat brain with treadmill exercise.
abstract: Neurotrophin 4 (NT-4) belongs to the family of neurotrophic factors, and it interacts with the tyrosine kinase B (trkB) receptor. NT-4 has neuroprotective effects following cerebral ischemia. Its role might be similar to brain-derived neurotrophic factor (BDNF), because both interact with trkB. Exercise also improves neural function by increasing neurotrophic factors. However, expression profiles of NT-4 in the brain during exercise are unknown. Here, we assessed the expressions of NT-4 and its receptor, trkB, following cerebral ischemia and hypothesized that exercise changes the expressions of NT-4 and trkB. Results showed that in a permanent middle cerebral artery occlusion rat model, ischemia decreased NT-4 and trkB expression. Immunohistochemistry showed their immunoreactivities around the region of the ischemic area. Treadmill exercise changed the expression of NT-4, which increased in the contralateral hemisphere in rats with ischemic injury. TrkB also showed similar patterns to its neurotophins. The change in NT-4 suggested that exercise might have primed NT4 production so that further injury causes slightly greater increases in NT4 compared with non-exercise controls.
authors.affiliation: Department of Neurology, Seoul National University Hospital, Chongno-ku, Seoul, Korea.
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Chung
authors.forename: Min-Wook
authors.initials: MW
authors.lastname: Kim
authors.forename: Moon-Suk
authors.initials: MS
authors.lastname: Bang
authors.forename: Manho
authors.initials: M
authors.lastname: Kim
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D007150:Immunohistochemistry; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism; D008297:Male; D008970:Molecular Weight; D009414:Nerve Growth Factors / Q000737:chemistry / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020813:Receptor, trkB / Q000737:chemistry / Q000378:metabolism
chemical_list: D009414:Nerve Growth Factors; D020813:Receptor, trkB; C073922:neurotrophin 4