RT Journal Article
SR Electronic
T1 Sensory Deprivation Disrupts Homeostatic Regeneration of Newly Generated Olfactory Sensory Neurons after Injury in Adult Mice
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 2657
OP 2673
DO 10.1523/JNEUROSCI.2484-14.2015
VO 35
IS 6
A1 Shu Kikuta
A1 Takashi Sakamoto
A1 Shin Nagayama
A1 Kaori Kanaya
A1 Makoto Kinoshita
A1 Kenji Kondo
A1 Koichi Tsunoda
A1 Kensaku Mori
A1 Tatsuya Yamasoba
YR 2015
UL http://www.jneurosci.org/content/35/6/2657.abstract
AB Although it is well known that injury induces the generation of a substantial number of new olfactory sensory neurons (OSNs) in the adult olfactory epithelium (OE), it is not well understood whether olfactory sensory input influences the survival and maturation of these injury-induced OSNs in adults. Here, we investigated whether olfactory sensory deprivation affected the dynamic incorporation of newly generated OSNs 3, 7, 14, and 28 d after injury in adult mice. Mice were unilaterally deprived of olfactory sensory input by inserting a silicone tube into their nostrils. Methimazole, an olfactotoxic drug, was also injected intraperitoneally to bilaterally ablate OSNs. The OE was restored to its preinjury condition with new OSNs by day 28. No significant differences in the numbers of olfactory marker protein-positive mature OSNs or apoptotic OSNs were observed between the deprived and nondeprived sides 0–7 d after injury. However, between days 7 and 28, the sensory-deprived side showed markedly fewer OSNs and mature OSNs, but more apoptotic OSNs, than the nondeprived side. Intrinsic functional imaging of the dorsal surface of the olfactory bulb at day 28 revealed that responses to odor stimulation were weaker in the deprived side compared with those in the nondeprived side. Furthermore, prevention of cell death in new neurons 7–14 d after injury promoted the recovery of the OE. These results indicate that, in the adult OE, sensory deprivation disrupts compensatory OSN regeneration after injury and that newly generated OSNs have a critical time window for sensory-input-dependent survival 7–14 d after injury.