Na_v1.7 is the predominant sodium channel in rodent olfactory sensory neurons

• Main Authors: Black Joel A (Author), Ahn Hye-Sook (Author), Zhao Peng (Author), Tyrrell Lynda (Author), Waxman Stephen G (Author), Dib-Hajj Sulayman D (Author)
• Format: Book
• Published: SAGE Publishing, 2011-05-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

<p>Abstract</p> <p>Background</p> <p>Voltage-gated sodium channel Na_v1.7 is preferentially expressed in dorsal root ganglion (DRG) and sympathetic neurons within the peripheral nervous system. Homozygous or compound heterozygous loss-of-function mutations in <it>SCN9A</it>, the gene which encodes Na_v1.7, cause congenital insensitivity to pain (CIP) accompanied by anosmia. Global knock-out of Na_v1.7 in mice is neonatal lethal reportedly from starvation, suggesting anosmia. These findings led us to hypothesize that Na_v1.7 is the main sodium channel in the peripheral olfactory sensory neurons (OSN, also known as olfactory receptor neurons).</p> <p>Methods</p> <p>We used multiplex PCR-restriction enzyme polymorphism, <it>in situ </it>hybridization and immunohistochemistry to determine the identity of sodium channels in rodent OSNs.</p> <p>Results</p> <p>We show here that Na_v1.7 is the predominant sodium channel transcript, with low abundance of other sodium channel transcripts, in olfactory epithelium from rat and mouse. Our <it>in situ </it>hybridization data show that Na_v1.7 transcripts are present in rat OSNs. Immunostaining of Na_v1.7 and Na_v1.6 channels in rat shows a complementary accumulation pattern with Na_v1.7 in peripheral presynaptic OSN axons, and Na_v1.6 primarily in postsynaptic cells and their dendrites in the glomeruli of the olfactory bulb within the central nervous system.</p> <p>Conclusions</p> <p>Our data show that Na_v1.7 is the dominant sodium channel in rat and mouse OSN, and may explain anosmia in Na_v1.7 null mouse and patients with Na_v1.7-related CIP.</p>

Item Description

10.1186/1744-8069-7-32
1744-8069