Constitutive ?-opioid receptor activity leads to long-term endogenous analgesia and dependence.
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ABSTRACT:
SUBMITTER: Corder G
PROVIDER: S-EPMC4440417 | biostudies-literature | 2013 Sep
REPOSITORIES: biostudies-literature
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Constitutive μ-opioid receptor activity leads to long-term endogenous analgesia and dependence.
Corder G G Doolen S S Donahue R R RR Winter M K MK Jutras B L BL He Y Y Hu X X Wieskopf J S JS Mogil J S JS Storm D R DR Wang Z J ZJ McCarson K E KE Taylor B K BK
Science (New York, N.Y.) 20130901 6152
Opioid receptor antagonists increase hyperalgesia in humans and animals, which indicates that endogenous activation of opioid receptors provides relief from acute pain; however, the mechanisms of long-term opioid inhibition of pathological pain have remained elusive. We found that tissue injury produced μ-opioid receptor (MOR) constitutive activity (MOR(CA)) that repressed spinal nociceptive signaling for months. Pharmacological blockade during the posthyperalgesia state with MOR inverse agonist ...[more]
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