Relationship of NK3 receptor-immunoreactivity to subpopulations of neurons in rat spinal cord.
The distribution of immunoreactivity to the neurokinin3 receptor (NK3R) was examined in segments C7, T11-12, L1-2, and L4-6 of the rat spinal cord. NK3R immunoreactivity was visualized by using two antisera generated against sequences of amino acids contained in the C-terminal region of the NK3R. NK3R-immunoreactive cells were numerous in the substantia gelatinosa of all spinal segments examined as well as the dorsal commissural nucleus of spinal segments L1-2. Isolated, immunoreactive cells were scattered throughout other regions of the spinal cord. The relationship of NK3R-immunoreactivity with neurons was demonstrated by colocalization with microtubule associated protein 2-immunoreactivity in individual cells. Within neurons, NK3R-immunoreactivity was associated predominately with the plasma membrane of cell bodies and dendrites. Within the substantia gelatinosa, 86% of nitric oxide synthase (NOS)-immunoreactive neurons were also NK3R-immunoreactive. Although NOS-immunoreactive neurons were found throughout all other regions of the spinal cord in the segments examined, these were not NK3R-immunoreactive. When preganglionic sympathetic neurons in spinal segments T11-12 and L1-2 were visualized by intraperitoneal injection of Fluorogold, less than 1% of the Fluorogold-labeled neurons were also immunoreactive for NK3R. The large number of NK3R-immunoreactive neurons in the substantia gelatinosa suggests that some effects of tachykinins on somatosensation may be mediated by NK3R.
Seybold
V S
VS
Department of Anatomy and Cell Biology, University of Melbourne, Victoria, Australia. ginger@med.umn.edu
Grkovic
I
I
Portbury
A L
AL
Ding
Y Q
YQ
Shigemoto
R
R
Mizuno
N
N
Furness
J B
JB
Southwell
B R
BR
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D005456:Fluorescent Dyes; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D007106:Immune Sera; D008297:Male; D008869:Microtubule-Associated Proteins / Q000032:analysis; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D018042:Receptors, Neurokinin-3 / Q000032:analysis*; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism*; D013266:Stilbamidines; D013376:Substantia Gelatinosa / Q000166:cytology / Q000378:metabolism
C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D005456:Fluorescent Dyes; D005904:Glial Fibrillary Acidic Protein; D007106:Immune Sera; D008869:Microtubule-Associated Proteins; D018042:Receptors, Neurokinin-3; D013266:Stilbamidines; D019001:Nitric Oxide Synthase