Multiple opioid peptides and the modulation of pain: Immunohistochemical analysis of dynorphin and enkephalin in the trigeminal nucleus caudalis and spinal cord of the cat
- 9 October 1985
- journal article
- research article
- Published by Wiley in Journal of Comparative Neurology
- Vol. 240 (4), 331-348
- https://doi.org/10.1002/cne.902400402
Abstract
Using immunocytochemistry we have identified important differences in the distribution of immunoreactive dynorphin and enkephalin cells and terminals in the trigeminal nucleus caudalis and in the spinal dorsal horn of the cat. Dynorphin immunoreactive processes are more closely associated with those regions of cord that process nociceptive information, specifically laminae I and V. Enkephalin neurons and terminals are more widespread. Based on the staining pattern with an antiserum to the octapeptide-met-enkephalin-arg-gly-leu, we suggest that the dense enkephalin terminal immunoreactivity in the inner part of the substantia gelatinosa derives from cells in lamina III. There are also significant differences in the anatomical relationship of the two opioid peptides with the organization of parasympatheic autonomic preganglionic neurons. The functional significance of these observations must await physiological analysis; nevertheless, it is almost certain that differences will be found and that these will be important in understanding the mechanisms through which exogenous opiates and a variety of descending control systems exert their effects on spinal cord neurons.Keywords
This publication has 62 references indexed in Scilit:
- Multiple endogenous opioid peptidesTrends in Neurosciences, 1983
- Analgesic effects of μ-, δ- and κ-opiate agonists and, in particular, dynorphin at the spinal levelLife Sciences, 1983
- The role of neuropeptides in the sacral autonomic reflex pathways of the catJournal of the Autonomic Nervous System, 1983
- Immunoreactive Vasoactive Intestinal Polypeptide Is Concentrated in the Sacral Spinal Cord: A Possible Marker for Pelvic Visceral Afferent FibersSomatosensory Research, 1983
- Dynorphin immunocytochemistry in the rat central nervous systemPeptides, 1982
- Immunohistochemical localization of dynorphin(1–8) in hypothalamic magnocellular neurons: Evidence for absence of proenkephalinLife Sciences, 1982
- Dynorphin: Potent analgesic effect in spinal cord of the ratLife Sciences, 1982
- U-50488H, a pure kappa receptor agonist with spinal analgesic loci in the mouseLife Sciences, 1982
- Multiple opiate receptor sites on primary afferent fibresNature, 1980
- Three bulbospinal pathways from the rostral medulla of the cat: An autoradiographic study of pain modulating systemsJournal of Comparative Neurology, 1978