Isolectin B(4)-positive and -negative nociceptors are functionally distinct. J Neurosci 1999 Aug 01;19(15):6497-505
Date
07/22/1999Pubmed ID
10414978Pubmed Central ID
PMC6782829DOI
10.1523/JNEUROSCI.19-15-06497.1999Scopus ID
2-s2.0-0033178342 (requires institutional sign-in at Scopus site) 406 CitationsAbstract
Small-diameter sensory neurons that are primarily nociceptors can be divided neurochemically into two populations: isolectin B(4) (IB(4))-positive nonpeptidergic neurons, and IB(4)-negative peptidergic neurons. It has been shown that IB(4)-positive neurons depend on glial-derived neurotrophic factor (GDNF), whereas IB(4)-negative neurons depend on NGF for survival during postnatal development (Molliver et al., 1997). Furthermore, these two populations of nociceptors terminate in distinct regions of the superficial spinal cord. To date, however, no evidence exists that indicates whether these two groups of nociceptors have distinct functional roles in the process of nociception (Snider and McMahon, 1998). To search for functional differences, we performed whole-cell voltage and current-clamp recordings on acutely isolated adult mouse dorsal root ganglion neurons that were labeled with fluorescent IB(4). We found that IB(4)-positive neurons have longer-duration action potentials, higher densities of TTX-resistant sodium currents, and smaller noxious heat-activated currents than IB(4)-negative neurons. Furthermore, we show that NGF, but not GDNF, directly increases the number of neurons that respond to noxious heat. The different electrophysiological properties expressed by IB(4)-positive and -negative small neurons, including their different heat sensitivities, indicates that they may relay distinct aspects of noxious stimuli both acutely and after injury in vivo.
Author List
Stucky CL, Lewin GRAuthor
Cheryl L. Stucky PhD Professor in the Cell Biology Neurobiology and Anatomy department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Action PotentialsAnimals
Drug Resistance
Electric Conductivity
Hot Temperature
Lectins
Mice
Mice, Inbred C57BL
Nerve Growth Factors
Neurons, Afferent
Nociceptors
Patch-Clamp Techniques
Sodium Channels
Tetrodotoxin
