title: Antagonization of fentanyl-induced muscular rigidity by denervation of the coerulospinal noradrenergic pathway in the rat.
abstract: The present study examined the effect of denervating the coerulospinal noradrenergic pathway on the muscular rigidity elicited by fentanyl in Sprague-Dawley rats anesthetized with ketamine. We demonstrated that the dopamine-beta-hydroxylase-positive nerve terminals arborizing on spinal motoneurons that innervate the sacrococcygeus dorsi lateralis (SCDL) muscle were significantly eliminated by DSP4 treatment. Unilateral microinjection of fentanyl (2.5 micrograms/50 nl) into the locus coeruleus of these animals also failed to evoke discernible increase in the electromyographic activity recorded from the SCDL muscle. These results lend further support for our previous finding that the coerulospinal noradrenergic neurotransmission is critically involved in fentanyl-induced muscular rigidity.
authors.affiliation: Department of Anesthesiology, National Yang-Ming Medical College, Taipei, Taiwan, ROC.
authors.forename: P W
authors.initials: PW
authors.lastname: Lui
authors.forename: G J
authors.initials: GJ
authors.lastname: Chang
authors.forename: T Y
authors.initials: TY
authors.lastname: Lee
authors.forename: S H
authors.initials: SH
authors.lastname: Chan
mesh_terms: D000818:Animals; D001596:Benzylamines / Q000633:toxicity; D015415:Biomarkers; D004299:Dopamine beta-Hydroxylase / Q000032:analysis; D004576:Electromyography; D005283:Fentanyl / Q000037:antagonists & inhibitors*; D008125:Locus Coeruleus / Q000187:drug effects / Q000503:physiopathology* / Q000648:ultrastructure; D008297:Male; D009046:Motor Neurons / Q000737:chemistry / Q000187:drug effects; D009121:Muscle Denervation; D009127:Muscle Rigidity / Q000139:chemically induced* / Q000503:physiopathology; D009419:Nerve Tissue Proteins / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000503:physiopathology* / Q000648:ultrastructure
chemical_list: D001596:Benzylamines; D015415:Biomarkers; D009419:Nerve Tissue Proteins; D004299:Dopamine beta-Hydroxylase; C012102:DSP 4; D005283:Fentanyl