TY - JOUR
T1 - The difference of osteocalcin-immunoreactive neurons in the rat dorsal root and trigeminal ganglia
T2 - Co-expression with nociceptive transducers and central projection
AU - Ichikawa, Hiroyuki
AU - Sugimoto, Tomosada
N1 - Funding Information:
We greatly appreciate Dr. David Julius at the Department of Cellular and Molecular Pharmacology, University of California for his kind gift of the anti-VRL-1-serum. This work was supported by a grant from the Japanese Ministry of Education, Culture, Sports, Science and Technology to H.I. (No. 14571733).
PY - 2002/12/27
Y1 - 2002/12/27
N2 - The co-expression of osteocalcin (OC) with the capsaicin receptor (VR1) and vanilloid receptor 1-like receptor (VRL-1) was examined in the dorsal root (DRG) and trigeminal ganglia (TG). Virtually all OC-immunoreactive (ir) DRG neurons were devoid of VR1- and VRL-1-immunoreactivity (ir). In the TG, 14.1% of OC-ir neurons were also immunoreactive for VR1. Only 1.7% of OC-ir TG neurons co-expressed VRL-1-ir. The distribution of OC-ir was also examined in the spinal cord and trigeminal sensory nuclei. In the spinal cord, the superficial laminae of the dorsal horn were devoid of OC-ir. The neuropil was weakly stained in other regions of the spinal horns. The medullary dorsal horn (MDH) contained numerous OC-ir varicose fibers in laminae I and II. These fibers were occasionally observed originating from the spinal trigeminal tract. The neuropil was weakly stained in deeper laminae of the MDH, and the rostral parts of the trigeminal sensory nuclei. The present study suggests that OC-ir TG nociceptors send their unmyelinated axons to the superficial laminae of the MDH.
AB - The co-expression of osteocalcin (OC) with the capsaicin receptor (VR1) and vanilloid receptor 1-like receptor (VRL-1) was examined in the dorsal root (DRG) and trigeminal ganglia (TG). Virtually all OC-immunoreactive (ir) DRG neurons were devoid of VR1- and VRL-1-immunoreactivity (ir). In the TG, 14.1% of OC-ir neurons were also immunoreactive for VR1. Only 1.7% of OC-ir TG neurons co-expressed VRL-1-ir. The distribution of OC-ir was also examined in the spinal cord and trigeminal sensory nuclei. In the spinal cord, the superficial laminae of the dorsal horn were devoid of OC-ir. The neuropil was weakly stained in other regions of the spinal horns. The medullary dorsal horn (MDH) contained numerous OC-ir varicose fibers in laminae I and II. These fibers were occasionally observed originating from the spinal trigeminal tract. The neuropil was weakly stained in deeper laminae of the MDH, and the rostral parts of the trigeminal sensory nuclei. The present study suggests that OC-ir TG nociceptors send their unmyelinated axons to the superficial laminae of the MDH.
KW - Immunohistochemistry
KW - Osteocalcin
KW - Trigeminal ganglion
KW - Trigeminal sensory nucleus
KW - VR1
KW - VRL-1
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U2 - 10.1016/S0006-8993(02)03701-0
DO - 10.1016/S0006-8993(02)03701-0
M3 - Article
C2 - 12470885
AN - SCOPUS:0037184690
SN - 0006-8993
VL - 958
SP - 459
EP - 462
JO - Molecular Brain Research
JF - Molecular Brain Research
IS - 2
ER -