[Retracted] β-Elemene Improves Morphine Tolerance in Bone Cancer Pain via N-Methyl-D-Aspartate Receptor 2B Subunit-Mediated μ-Opioid Receptor

Figure 1

The effects of β-Elemene on the morphine-induced tolerance and the related protein expressions. (a) The mechanical withdrawal threshold of rats was detected by mechanical allodynia test. (b) The thermal withdrawal latency of rats was detected by thermal hyperalgesia test. (c-e) The expressions of MOPR, cAMP and NR2B and the ratio of p-CaMKII to CaMKII were determined by western blot, with β-actin as the internal reference. All experiments were repeated three times to obtain average values. The data are presented as the of three independent experiments; ; ; vs. Control; ; ; vs. MT. Abbreviations: MOPR: μ-opioid receptor; cAMP: cyclic adenosine monophosphate; NR2B: N-methyl-D-aspartate receptor subunit 2B; p-CaMKII: phosphorylated-calmodulin-dependent protein kinase II.

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