Puehler W, Zöllner C, Brack A, Shaqura M A, Krause H, Schäfer M, Stein C
Klinik für Anaesthesiologie und operative Intensivmedizin, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, D-12200 Berlin, Germany.
Neuroscience. 2004;129(2):473-9. doi: 10.1016/j.neuroscience.2004.06.086.
S.c. painful inflammation leads to an increase in axonal transport of opioid receptors from dorsal root ganglia (DRG) toward the periphery, thus causing a higher receptor density and enhanced opioid analgesia at the injured site. To examine whether this increase is related to transcription, the mRNA of Delta- (DOR) and mu-opioid receptor (MOR) in lumbar DRG was quantified by real time Light Cycler polymerase chain reaction (LC-PCR), and correlated to ligand binding in DRG and sciatic nerve. In normal DRG, DOR mRNA was seven times less abundantly expressed than MOR mRNA. After induction of unilateral paw inflammation, mRNA content for DOR remained unchanged, but a bi-phasic upregulation for MOR mRNA with an early peak at 1-2 h and a late increase at 96 h was found in ipsilateral DRG. As no changes were observed in DRG of the non-inflamed side, this effect was apparently not systemically mediated. A significant increase in binding of the MOR ligand DAMGO was detected after 24 h in DRG, and after early and late ligation in the sciatic nerve, indicating an enhanced axonal transport of MOR in response to inflammation. The early increase in MOR mRNA could be completely prevented by local anesthetic blockade of neuronal conduction in sciatic nerve. These data suggest that mRNA of the two opioid receptors DOR and MOR is differentially regulated in DRG during peripheral painful inflammation. The apparently increased axonal transport of MOR in response to this inflammation is preceded by upregulated mRNA-transcription, which is dependent on neuronal electrical activity.
皮下疼痛性炎症导致阿片受体从背根神经节（DRG）向周围的轴突运输增加，从而在损伤部位引起更高的受体密度和增强的阿片类镇痛作用。为了研究这种增加是否与转录有关，通过实时荧光定量聚合酶链反应（LC-PCR）对腰段DRG中δ-阿片受体（DOR）和μ-阿片受体（MOR）的mRNA进行定量，并与DRG和坐骨神经中的配体结合相关联。在正常DRG中，DOR mRNA的表达丰度比MOR mRNA低7倍。在诱导单侧爪部炎症后，DOR的mRNA含量保持不变，但在同侧DRG中发现MOR mRNA呈双相上调，早期峰值出现在1-2小时，晚期增加出现在96小时。由于在未发炎侧的DRG中未观察到变化，这种效应显然不是由全身介导的。在DRG中，24小时后检测到MOR配体DAMGO的结合显著增加，在坐骨神经早期和晚期结扎后也增加，表明炎症反应中MOR的轴突运输增强。坐骨神经局部麻醉阻断神经元传导可完全阻止MOR mRNA的早期增加。这些数据表明，在周围疼痛性炎症期间，DRG中两种阿片受体DOR和MOR的mRNA受到不同调节。这种炎症反应中MOR轴突运输的明显增加之前是mRNA转录上调，这依赖于神经元电活动。
