Journal of Neuroscience, Vol 5, 1833-1841, Copyright © 1985 by Society for Neuroscience
Immunocytochemical studies of the peptidergic content of fibers and terminals within the lateral spinal and lateral cervical nuclei
GJ Giesler Jr and RP Elde
As part of a series of studies in which we are attempting to determine the
roles of the lateral spinal (LSn) and lateral cervical (LCn) nuclei in
somatic sensation, we have examined the fibers and terminals within these
nuclei in the rat using the indirect immunofluorescence technique. Eleven
antisera were used. Within the LSn, antisera against dynorphin 1-8 (DYN),
substance P (SP), and Met-enkephalin (ENK) produced labeling of a large
number of processes in all segmental levels examined. Processes labeled
with these antisera frequently apposed the cell bodies and dendrites of LSn
neurons. Antisera against somatostatin (SOM) and FMRF-NH2 (FMRF) labeled
smaller numbers of processes within the LSn. Few, if any, processes in the
LSn were labeled using antisera against serotonin, cholecystokinin
octapeptide, oxytocin, neurotensin, corticotrophin-releasing factor, and
vasoactive intestinal polypeptide. In contrast to the LSn, the LCn
contained virtually no labeled processes irrespective of the antiserum
employed. An area was found adjacent to the LCn in the medial portion of
the dorsal lateral funiculus (DLf) of C2 that resembled the LSn in several
of its anatomical characteristics: like the LSn, the medial portion of the
C2 DLf contained small multipolar neurons; it was similar to the LSn in its
medial-lateral extent; and following staining with each antiserum, the LSn
and the medial DLf of C2 contained a similar number of labeled processes.
The peptide-containing area in the medial DLf of C2 was found to be
continuous with the LSn. We therefore propose that this region is a rostral
extension of the LSn.(ABSTRACT TRUNCATED AT 250 WORDS)