Demonstration of calcitonin gene-related peptide immunoreactive axons contacting dynorphin A(1-8) immunoreactive spinal neurons in a rat model of peripheral inflammation and hyperalgesia.
In a rat model of peripheral inflammation and hyperalgesia, dynorphin A(1-8)-like immunoreactive (DYN-LIr) spinal neurons were examined for contacts from calcitonin gene-related peptide-like immunoreactive (CGRP-LIr) varicosities using a double-label PAP method. Ipsilateral to the inflammation, CGRP-LIr varicosities contacted both dendrites and somata of DYN-LIr neurons in lumbar laminae I, II and V. Few such contacts were found on the contralateral side. The results suggest that opioid neurons which exhibit a dynamic change in dynorphin associated with inflammation, represent a subpopulation of neurons that receive contacts from presumptive nociceptive primary afferents.
Takahashi
O
O
Neurobiology and Anesthesiology Branch, National Institute of Dental Research, Bethesda, MD 20892.
Traub
R J
RJ
Ruda
M A
MA
D000818:Animals; D015740:Calcitonin Gene-Related Peptide; D002452:Cell Count; D004399:Dynorphins / Q000378:metabolism*; D006930:Hyperalgesia / Q000378:metabolism*; D006941:Hyperesthesia / Q000378:metabolism*; D007150:Immunohistochemistry; D007249:Inflammation / Q000378:metabolism*; D008297:Male; D009479:Neuropeptides / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D010523:Peripheral Nervous System Diseases / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D013569:Synapses / Q000378:metabolism / Q000473:pathology
D009479:Neuropeptides; D010446:Peptide Fragments; D004399:Dynorphins; C026770:dynorphin (1-8); D015740:Calcitonin Gene-Related Peptide