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

Figure 3

The effects of NMDA on the cAMP content and related protein expressions in SH-SY5Y cells. (a) The intracellular cAMP content was measured by the LANCE cAMP kit. (b–d) The ratio of p-CaMKII to CaMKII, and the expressions of MOPR, cAMP, and NR2B 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; vs. β-Elemene. Abbreviations: NMDA: N-methyl-D-aspartic acid; 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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