Fighting in the aged male mouse increases the expression of TrkA and TrkB in the subventricular zone and in the hippocampus.
In the present study, we investigate the effect of aggressive behavior and release of nerve growth factor (NGF) on brain progenitor cells. We found that the condition of subordination enhances the level of NGF in the subventricular zone and hippocampus whereas dominance elevates brain derived neurotrophic factor (BDNF). It was also found that mRNA-TrkA is over-expressed in the subventricular zone and hippocampus of dominant and subordinate mice, whereas mRNA-TrkB is increased in the subventricular zone of both dominants and subordinates and in the hippocampus of dominant mice. Fighting was also associated with increased presence of proliferating cells in the hippocampus stained with the nuclear marker bromodeoxyuridine (BrdU). Moreover, the brain of subordinate mice displayed tyrosine hydroxylase (TH) immunoreactivity in the wall of the periventricular region of the third ventricles and a marked neuropeptide Y (NPY) presence in the hippocampus co-expressed with BrdU. These results provide additional evidence that agonistic behavior in the aged mouse alters neurotrophin levels and increases brain progenitor cells number. The functional significance of these findings is discussed.
Fiore
Marco
M
Istituto di Neurobiologia e Medicina Molecolare, Sezione di Neurobiologia, CNR, Viale Marx, 43/15, 00137 Rome, Italy.
Amendola
Tiziana
T
Triaca
Viviana
V
Alleva
Enrico
E
Aloe
Luigi
L
D000374:Aggression / Q000502:physiology*; D000375:Aging / Q000502:physiology*; D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D049109:Cell Proliferation; D004291:Dominance-Subordination; D004805:Ependyma / Q000166:cytology / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051379:Mice; D009478:Neuropeptide Y / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D020917:Receptor, trkA / Q000235:genetics / Q000378:metabolism*; D020813:Receptor, trkB / Q000235:genetics / Q000378:metabolism*; D013234:Stem Cells / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D019208:Brain-Derived Neurotrophic Factor; D009478:Neuropeptide Y; D012333:RNA, Messenger; D014446:Tyrosine 3-Monooxygenase; D020917:Receptor, trkA; D020813:Receptor, trkB