NOCICEPTIN-LIKE IMMUNOREACTIVITY IN AUTONOMIC NUCLEI OF THE RAT SPINAL-CORD

Immunohistochemical techniques were used to localize nociceptin-like i mmunoreactivity (NOCI-LI) in the rat spinal cords. NOCI-LI nerve fiber s were distributed in three fairly well-defined regions: superficial l ayers of the dorsal horn, central canal area, and intermediolateral ce ll column (ILp) of lower cervical, thoracic, upper lumbar, and sacral segments of the spinal cord. A few NOCI-LI somata of small diameter we re noted in the dorsal horn; NOCI-LI cell bodies were infrequently obs erved in the ILp or ventral horn. Concentration of NOCI-LI in nerve fi bers of the superficial layers and in fibers projecting into the spina l sympathetic and parasympathetic nuclei suggests that the peptide may participate in sensory as well as autonomic functions. (C) 1997 Elsev ier Science Ireland Ltd.