Dopamine enhancement of dextrorphan-induced skin antinociception in response to needle pinpricks in rats

Yu Yu Li, Chong Chi Chiu, Jhi Joung Wang, Yu Wen Chen, Ching Hsia Hung

研究成果: Article

2 引文 斯高帕斯(Scopus)

摘要

Background: Dextrorphan with long-acting local anesthetic effects did not cause system toxicity as fast as bupivacaine, while catecholamines (i.e., epinephrine) with the vasoconstrictive characteristics enhanced the effects of local anesthetic drugs. The objective of the experiment was to examine the synergistic effect of local dopamine (a catecholamine) injection on cutaneous antinociception of dextrorphan. Methods: The panniculus reflex in response to skin stimulation with a needle was used as the primary endpoint when dextrorphan (1.50, 2.61, 5.46, 10.20 and 20.40 μmol) alone, dopamine (16.20, 32.40, 51.60, 60.00 and 81.60 μmol) alone, or dopamine + dextrorphan (a ratio of ED50 vs. ED50) was injected subcutaneously on the rat's back. We used an isobolographic modelling approach to determine whether a synergistic effect would be observed. Results: We showed that dextrorphan, dopamine, or the mixture of dopamine and dextrorphan produced dose-related skin antinociception. The potency (ED50, 50% effective dose) for cutaneous antinociception was dextrorphan [6.02 (5.93–6.14) μmol] greater than dopamine [48.91 (48.80–49.06) μmol] (p < 0.01). The duration of nociceptive inhibition induced by dopamine was longer than that induced by dextrorphan (p < 0.01) based on their equipotent doses (ED25, ED50, and ED75). Enhancement and prolongation of skin antinociception occurred after co-administration of dopamine with dextrorphan. Conclusions: When compared to dopamine, dextrorphan was more potent and had a shorter duration of skin nociceptive block. Dopamine produced a synergistic effect on dextrorphan-mediated antinociception, and prolonged dextrorphan′s antinociceptive duration.

原文English
頁(從 - 到)732-737
頁數6
期刊Pharmacological Reports
71
發行號4
DOIs
出版狀態Published - 2019 八月

    指紋

All Science Journal Classification (ASJC) codes

  • Pharmacology

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