title: Gene and protein analysis of brain derived neurotrophic factor expression in relation to neurological recovery induced by an enriched environment in a rat stroke model.
abstract: Although an enriched environment enhances functional recovery after ischemic stroke, the mechanism underlying this effect remains unclear. We previously reported that brain derived neurotrophic factor (BDNF) gene expression decreased in rats housed in an enriched environment for 4 weeks compared to those housed in a standard cage for the same period. To further clarify the relationship between the decrease in BDNF and functional recovery, we investigated the effects of differential 2-week housing conditions on the mRNA of BDNF and protein levels of proBDNF and mature BDNF (matBDNF). After transient occlusion of the right middle cerebral artery of male Sprague-Dawley rats, we divided the rats into two groups: (1) an enriched group housed multiply in large cages equipped with toys, and (2) a standard group housed alone in small cages without toys. Behavioral tests before and after 2-week differential housing showed better neurological recovery in the enriched group than in the standard group. Synaptophysin immunostaining demonstrated that the density of synapses in the peri-infarct area was increased in the enriched group compared to the standard group, while infarct volumes were not significantly different. Real-time reverse transcription polymerase chain reaction, Western blotting and immunostaining all revealed no significant difference between the groups. The present results suggest that functional recovery cannot be ascribed to an increase in matBDNF or a decrease in proBDNF but rather to other underlying mechanisms.
authors: Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Japan.
authors: Kenji
authors: K
authors: Hirata
authors: Yuji
authors: Y
authors: Kuge
authors: Chiaki
authors: C
authors: Yokota
authors: Akina
authors: A
authors: Harada
authors: Koichi
authors: K
authors: Kokame
authors: Hiroyasu
authors: H
authors: Inoue
authors: Hidekazu
authors: H
authors: Kawashima
authors: Hiroko
authors: H
authors: Hanzawa
authors: Yuji
authors: Y
authors: Shono
authors: Hideo
authors: H
authors: Saji
authors: Kazuo
authors: K
authors: Minematsu
authors: Nagara
authors: N
authors: Tamaki
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics* / Q000378:metabolism*; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D005786:Gene Expression Regulation / Q000502:physiology*; D005910:Glioma / Q000378:metabolism; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000451:nursing*; D008297:Male; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function / Q000502:physiology*; D012931:Social Environment; D013997:Time Factors
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger