Latexin expression in smaller diameter primary sensory neurons in the rat

• Published in: Brain research 1998-08, Vol.801 (1), p.9-20
• Main Authors: Takiguchi-Hayashi, Keiko, Sato, Michio, Sugo, Noriyuki, Ishida, Mami, Sato, Kazuki, Uratani, Yoshihiko, Arimatsu, Yasuyoshi
• Format: Article
• Language: English
• Subjects: Animals; Antigens - analysis; Antigens - biosynthesis; Biological and medical sciences; Blotting, Western; Capsaicin - pharmacology; Cells, Cultured; Dorsal root ganglion; Fundamental and applied biological sciences. Psychology; Ganglia, Spinal - chemistry; Ganglia, Spinal - cytology; Ganglia, Spinal - drug effects; Immunohistochemistry; Microscopy, Immunoelectron; Nerve Tissue Proteins; Neurons, Afferent - chemistry; Neurons, Afferent - cytology; Neurons, Afferent - ultrastructure; Nociceptors - chemistry; Nociceptors - cytology; Pain; Rats; Rats, Wistar; Somesthesis and somesthetic pathways (proprioception, exteroception, nociception); interoception; electrolocation. Sensory receptors; Spinal cord; Spinal Cord - cytology; Spinal Cord - ultrastructure; Trigeminal ganglion; Vertebrates: nervous system and sense organs
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/S0006-8993(98)00496-X

Most of the smaller diameter neurons of dorsal root and trigeminal ganglia in adult rats expressed latexin, which has the inhibitor activity of carboxypeptidase A. Most of the dorsal root ganglion (DRG) neurons containing either calcitonin gene-related peptide (CGRP), substance P (SP) or somatostatin (SST) coexpressed latexin. Latexin was widely distributed in the cytoplasm of the cell body and in axonal fibers of cultured DRG neurons which were sensitive to capsaicin. In addition, latexin-immunoreactivity was observed throughout lamina II of the spinal cord in normal animals, but was lost following sciatic nerve-axotomy, suggesting the presence of latexin-immunoreactive axonal fibers and/or terminals from DRG neurons. Immunoelectron microscopy indeed revealed latexin-immunoreactive axonal terminals and thinly myelinated and unmyelinated axonal fibers within the dorsal horn. These observations suggest that latexin may be involved in nociceptive information transmission or its modulation.