Co-localization of proenkephalin- and prodynorphin-derived opioid peptides in laminae IV/V spinal neurons revealed in arthritic rats.
By the use of highly selective antisera and an immunohistochemical technique the possible coexistence of proenkephalin- (PRO-ENK)- and prodynorphin (PRO-DYN)-derived peptides was examined in 4- to 6-micron thick serial sections of the L4-L5 segments of the spinal cord of non-colchicine-treated polyarthritic rats. In control, non-colchicine treated animals, virtually no cell bodies stained for the PRO-ENK-derived peptides, heptapeptide (MRF) and octapeptide (MRGL), nor for the PRO-DYN-derived peptides, dynorphin A (DYN) and alpha-neoendorphin (NEO). In contrast, in polyarthritic rats, numerous large (15-30 micron) multipolar neurons could be visualized with each antiserum in laminae IV/V. Alternate staining of adjacent sections with either anti-MRF or anti-MRGL antisera, followed by either anti-DYN or anti-NEO antisera, revealed a clear coexistence of PRO-ENK and PRO-DYN peptides. It was possible to demonstrate co-localization of all 4 opioids in a single cell. It appeared that all cells staining for PRO-ENK peptides in laminae IV/V also stained for PRO-DYN peptides.
D000818:Animals; D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D004399:Dynorphins / Q000378:metabolism; D004723:Endorphins / Q000378:metabolism*; D004745:Enkephalins / Q000378:metabolism*; D008297:Male; D009842:Oligopeptides / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000378:metabolism* / Q000473:pathology
D004723:Endorphins; D004745:Enkephalins; D009842:Oligopeptides; D011498:Protein Precursors; C029992:proenkephalin; C025681:alpha-neoendorphin; D004399:Dynorphins; C033660:preproenkephalin