Effects of chronic exercise and imipramine on mRNA for BDNF after olfactory bulbectomy in rat.
We examined the effects of chronic activity wheel running and antidepressant treatment on brain-derived neurotrophic factor (BDNF) messenger RNA (mRNA) in multiple brain regions-hippocampal formation (HF), ventral tegmental area/substantia nigra (VTA/SN), nucleus accumbens (NAc), and piriform cortex (PFx)-after bilateral olfactory bulbectomy (OBX). Male, Long-Evans rats (n=72) underwent either sham or OBX surgery and were randomly divided into eight experimental groups in a 2 (sham vs. OBX) x 2 (sedentary vs. activity wheel)x2 (saline vs. imipramine) factorial design. Animals were killed after 21 days of treatment. Drug x exercise interaction effects were observed for HF (P=0.006-0.023) and VTA/SN (P=0.021); exercise increased BDNF mRNA in the saline treated animals but not in the imipramine treated animals. OBX did not affect BDNF mRNA in the HF or VTA/SN (P>0.05). BDNF mRNA levels in the PFx were not altered by exercise, drug, or OBX (P>0.05). These results suggest that the effect of exercise on BDNF mRNA extends beyond the HF to the mesolimbic ventral tegmental area and that the potentiation of BDNF mRNA by exercise and antidepressant pharmacotherapy, reported by other investigators, is time limited.
Department of Exercise Science, University of Georgia, 300 River Rd., Athens 30602, USA.
Jacqueline D
JD
Van Hoomissen
Heather O
HO
Chambliss
Philip V
PV
Holmes
Rod K
RK
Dishman
D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000494:pharmacology*; D001345:Autoradiography; D001522:Behavior, Animal / Q000502:physiology; D001923:Brain Chemistry / Q000187:drug effects / Q000502:physiology; D019208:Brain-Derived Neurotrophic Factor / Q000096:biosynthesis*; D007099:Imipramine / Q000494:pharmacology*; D017403:In Situ Hybridization; D008297:Male; D009830:Olfactory Bulb / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D020318:Rats, Long-Evans; D012420:Running / Q000502:physiology
D000929:Antidepressive Agents, Tricyclic; D019208:Brain-Derived Neurotrophic Factor; D012333:RNA, Messenger; D007099:Imipramine