PT  - JOURNAL ARTICLE
AU  - Christopher K. Thompson
AU  - Eliot A. Brenowitz
TI  - Neurogenesis in an Adult Avian Song Nucleus Is Reduced by Decreasing Caspase-Mediated Apoptosis
AID  - 10.1523/JNEUROSCI.5423-08.2009
DP  - 2009 Apr 08
TA  - The Journal of Neuroscience
PG  - 4586--4591
VI  - 29
IP  - 14
4099  - http://www.jneurosci.org/content/29/14/4586.short
4100  - http://www.jneurosci.org/content/29/14/4586.full
SO  - J. Neurosci.2009 Apr 08; 29
AB  - Neuron death and replacement are fundamental components of brain plasticity. Much remains unknown, however, about the mechanistic interaction between neuron death and neurogenesis in adult vertebrates. In seasonally breeding adult male white-crowned sparrows, the song system nucleus HVC loses ∼26% of its neurons via caspase-dependent apoptosis within 4 d after a transition to nonbreeding physiological conditions. To determine whether neuronal death is necessary for the recruitment of new neurons, we infused caspase inhibitors into HVC in vivo and suppressed neurodegeneration for at least 20 d after the transition to nonbreeding conditions. The blockade of HVC neuron death reduced the number and density of new neurons recruited to the ipsilateral HVC by 48 and 29%, respectively, compared with contralateral HVC. Our results are the first to show that reducing neuronal death in the adult brain decreases the recruitment of new neurons.