A novel knock-in mouse reveals mechanistically distinct forms of morphine tolerance.
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ABSTRACT:
SUBMITTER: Enquist J
PROVIDER: S-EPMC3141896 | biostudies-other | 2011 Aug
REPOSITORIES: biostudies-other
Publications
A novel knock-in mouse reveals mechanistically distinct forms of morphine tolerance.
Enquist Johan J Kim Joseph A JA Bartlett Selena S Ferwerda Madeline M Whistler Jennifer L JL
The Journal of pharmacology and experimental therapeutics 20110511 2
The role of μ-opioid receptor (MOR) down-regulation in opioid tolerance remains controversial. In this study, we used a novel knock-in mouse to examine how changing the extent of MOR down-regulation alters the development of morphine tolerance. These mice express a mutant MOR, degrading MOR (DMOR), that differs from the wild-type (WT) MOR in two ways: 1) unlike the recycling WT MOR, the mutant DMOR is targeted for degradation after its internalization, thus facilitating down-regulation; and 2) u ...[more]
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