The Journal of Neuroscience, September 15, 2001, 21(18):7236-7246
The Meissner Corpuscle Revised: A Multiafferented Mechanoreceptor
with Nociceptor Immunochemical Properties
Michel
Paré1,
Robert
Elde2,
Joseph E.
Mazurkiewicz3,
Allan M.
Smith1, and
Frank L.
Rice3
1 Département de Physiologie, Université de
Montréal, Montréal, Québec, Canada H3C 3J7,
2 Department of Neuroscience, University of Minnesota,
Minneapolis, Minnesota 55455, and 3 Center for
Neuropharmacology and Neuroscience, Albany Medical College, Albany, New
York 12208
Meissner corpuscles (MCs) in the glabrous skin of monkey digits
have at least three types of innervation as revealed by
immunofluorescence. The previously well known A
-fiber terminals
are closely intertwined with endings from peptidergic C-fibers. These
intertwined endings are segregated into zones that alternate with zones
containing a third type of ending supplied by nonpeptidergic C-fibers.
Although MCs are widely regarded as low-threshold mechanoreceptors, all three types of innervation express immunochemical properties associated with nociception. The peptidergic C-fiber endings have readily detectable levels of immunoreactivity (IR) for calcitonin gene-related peptide (CGRP) and substance P (SP). The A
endings have
relatively lower levels of IR for CGRP and SP as well as the SP
neurokinin 1 receptor and vanilloid-like receptor 1. Both the A
and peptidergic C-fiber endings were also labeled with antibodies for
different combinations of adrenergic, opioid, and purinergic receptors. The nonpeptidergic C-fiber endings express IR for vanilloid receptor 1, which has also been implicated in nociception. Thus, MCs are multiafferented receptor organs that may have nociceptive capabilities in addition to being low-threshold mechanoreceptors.
Key words:
digit; cutaneous innervation; Meissner corpuscle; primate; mechanoreceptors; nociceptors
Copyright © 2001 Society for Neuroscience 0270-6474/01/21187236-11$05.00/0