Loading…
Dorsal Root Ganglion Neurons Express Multiple Nicotinic Acetylcholine Receptor Subtypes
1 Committee on Neurobiology, 2 Committee on Cell Physiology, and 3 Department of Anesthesia and Critical Care, University of Chicago, Chicago, Illinois 60637 Genzen, Jonathan R., William Van Cleve, and Daniel S. McGehee. Dorsal Root Ganglion Neurons Express Multiple Nicotinic Acetylcholine Rec...
Saved in:
Published in: | Journal of neurophysiology 2001-10, Vol.86 (4), p.1773-1782 |
---|---|
Main Authors: | , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | 1 Committee on Neurobiology,
2 Committee on Cell Physiology, and
3 Department of Anesthesia and Critical
Care, University of Chicago, Chicago, Illinois 60637
Genzen, Jonathan R.,
William Van Cleve, and
Daniel S. McGehee.
Dorsal Root Ganglion Neurons Express Multiple Nicotinic
Acetylcholine Receptor Subtypes. J. Neurophysiol. 86: 1773-1782, 2001. Although nicotinic agonists can modulate
sensory transmission, particularly nociceptive signaling, remarkably
little is known about the functional expression of nicotinic
acetylcholine receptors (nAChRs) on primary sensory neurons. We have
utilized molecular and electrophysiological techniques to characterize
the functional diversity of nAChR expression on mammalian dorsal root
ganglion (DRG) neurons. RT-PCR analysis of subunit mRNA in DRG tissue
revealed the presence of nAChR subunits 2-7 and 2- 4. Using
whole cell patch-clamp recording and rapid application of nicotinic
agonists, four pharmacologically distinct categories of nicotinic
responses were identified in cultured DRG neurons. Capacitance
measurements were used to divide neurons into populations of large and
small cells, and the prevalence of nicotinic responses was compared between groups. Category I ( 7-like) responses were seen in 77% of
large neurons and 32% of small neurons and were antagonized by 10 nM
methyllycaconitine citrate (MLA) or or 50 nM -bungarotoxin ( -BTX). Category II ( 3 4-like) responses were seen in 16% of large neurons and 9% of small neurons and were antagonized by 20 µM
mecamylamine but not 10 nM MLA or 1 µM DH E. Category II responses
had a higher sensitivity to cytisine than nicotine. Two other types of
responses were identified in a much smaller percentage of neurons and
were classified as either category III ( 4 2-like) or category IV
(subtype unknown) responses. Both the 7-like and 3 4-like
responses could be desensitized by prolonged applications of the
analgesic epibatidine. |
---|---|
ISSN: | 0022-3077 1522-1598 |
DOI: | 10.1152/jn.2001.86.4.1773 |