The Journal of Neuroscience, September 1, 2001, 21(17):6706-6717
Infusion of Brain-Derived Neurotrophic Factor into the Lateral
Ventricle of the Adult Rat Leads to New Neurons in the Parenchyma of
the Striatum, Septum, Thalamus, and Hypothalamus
Viorica
Pencea1,
Kimberly D.
Bingaman1, 2,
Stanley J.
Wiegand3, and
Marla B.
Luskin1
Departments of 1 Cell Biology and
2 Neurosurgery, Emory University School of Medicine,
Atlanta, Georgia 30322, and 3 Regeneron Pharmaceuticals
Inc., Tarrytown, New York 10591
The findings that brain-derived neurotrophic factor (BDNF)
promotes in vitro the survival and/or differentiation of
postnatal subventricular zone (SVZ) progenitor cells and increases
in vivo the number of the newly generated neurons in the
adult rostral migratory stream and olfactory bulb prompted us to
investigate whether the infusion of BDNF influences the proliferation
and/or differentiation of cells in other regions of the adult
forebrain. We examined the distribution and phenotype of newly
generated cells in the adult rat forebrain 16 d after
intraventricular administration of BDNF in conjunction with the cell
proliferation marker bromodeoxyuridine (BrdU) for 12 d. BDNF
infusion resulted in numerous BrdU+ cells,
not only in the SVZ lining the infused lateral ventricle, but moreover,
in specific parenchymal structures lining the lateral and third
ventricles, including the striatum and septum, as well as the thalamus
and hypothalamus, in which neurogenesis had never been demonstrated
previously during adulthood. In each region, newly generated cells
expressed the neuronal marker microtubule-associated protein-2, or
neuron-specific tubulin, identified by the antibody TuJ1. The
percentage of the newly generated cells expressing TuJ1 ranged from 27 to 42%, suggesting that the adult forebrain has a more profound
capacity to produce neurons than recognized previously. The extent of
cell proliferation after BDNF infusion was correlated with the level of
expression of full-length TrkB, the high-affinity receptor for BDNF,
despite the fact that the BrdU+ cells were not
themselves TrkB+. Collectively, our results
demonstrate that the adult brain parenchyma may recruit and/or generate
new neurons, which could replace those lost as a result of
injury or disease.
Key words:
brain-derived neurotrophic factor; cell proliferation; forebrain parenchyma; intraventricular infusion; postnatal
neurogenesis; subventricular zone
Copyright © 2001 Society for Neuroscience 0270-6474/01/21176706-12$05.00/0