title: Changes in mu opiate receptors following inescapable shock.
abstract: Rats exposed to inescapable shock exhibit profound hypoalgesia. Pharmacological evidence has suggested that changes in endogenous opiate activity may be responsible for the hypoalgesic response. We measured the binding of [3H]DAGO, a selective mu-opiate receptor agonist, in brains of rats exposed to no shock, inescapable shock, or escapable shock. Binding of [3H]DAGO in the midbrains of rats in the inescapable shock group was decreased relative to the other two groups. The decrease in binding appeared to result from a decrease in number of mu-receptors and not a change in affinity. These results support the hypothesis that inescapable shock produces long-term changes in endogenous opiate systems.
authors.affiliation: Laboratory of Clinical Science, NIMH, Poolesville, MD 20837.
authors.forename: J
authors.initials: J
authors.lastname: Stuckey
authors.forename: S
authors.initials: S
authors.lastname: Marra
authors.forename: T
authors.initials: T
authors.lastname: Minor
authors.forename: T R
authors.initials: TR
authors.lastname: Insel
mesh_terms: D000818:Animals; D004597:Electroshock; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004745:Enkephalins / Q000378:metabolism; D008297:Male; D008636:Mesencephalon / Q000378:metabolism* / Q000503:physiopathology; D051381:Rats; D011957:Receptors, Opioid / Q000378:metabolism*; D017450:Receptors, Opioid, mu; D013312:Stress, Physiological / Q000378:metabolism*
chemical_list: D004745:Enkephalins; D011957:Receptors, Opioid; D017450:Receptors, Opioid, mu; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-