Department of Pharmacology, Faculty of Medicine, Ataturk University, 25240 Erzurum, Turkey.
Pharmacol Rep. 2011;63(2):518-26. doi: 10.1016/s1734-1140(11)70518-7.
A gastroprotective effect occurs when α(2) receptors are innervated. The dextro isomer of medetomidine, dexmedetomidine, is a highly selective α(2)-adrenoreceptor agonist. The aim of this study was to investigate whether dexmedetomidine has an antiulcerative effect and to show whether the antiulcer mechanism of dexmedetomidine is linked with oxidant/antioxidant parameters. The antiulcerative effect of dexmedetomidine was studied in an indomethacin-induced ulcer model, and some oxidant/antioxidant parameters were measured in these gastric tissues. Whereas the average ulcerous areas for the groups that received 10, 25, 50, and 100 μg/kg dexmedetomidine doses were 29 ± 4.2, 8 ± 2.1, 0 ± 0 and 0 ± 0 mm(2), respectively, the ulcerous area was 52.1 ± 4.5 mm(2) in the indomethacin control group and 0.5 ± 0.2 mm(2) in the famotidine group. In conclusion, the α(2)-adrenoreceptor agonist dexmedetomidine showed a significant antiulcerative effect in rat gastric tissue at all doses. This antiulcerative effect is stronger with increasing dosage; at the 50 and 100 μg/kg doses, no ulcerous areas were observed. In light of these results, we conclude that there is a correlation between antiulcer mechanisms and α(2)-receptor activation. In rats given dexmedetomidine, all of the investigated antioxidant parameters increased, except for catalase (CAT). Conversely, aside from myeloperoxidase (MPO), all oxidant parameters decreased. Therefore, oxidant/antioxidant parameters play a role in the antiulcer mechanism of dexmedetomidine.
当α(2)受体被支配时，就会产生胃保护作用。右美托咪定的右旋异构体，即右美托咪定，是一种高度选择性的α(2)-肾上腺素受体激动剂。本研究旨在探讨右美托咪定是否具有抗溃疡作用，并阐明右美托咪定的抗溃疡机制是否与氧化应激/抗氧化参数有关。在消炎痛诱导的溃疡模型中研究了右美托咪定的抗溃疡作用，并在这些胃组织中测量了一些氧化应激/抗氧化参数。接受 10、25、50 和 100μg/kg 右美托咪定剂量的各组的平均溃疡面积分别为 29±4.2、8±2.1、0±0 和 0±0mm(2)，而消炎痛对照组的溃疡面积为 52.1±4.5mm(2)，法莫替丁组为 0.5±0.2mm(2)。结论：在所有剂量下，α(2)-肾上腺素受体激动剂右美托咪定在大鼠胃组织中均表现出显著的抗溃疡作用。这种抗溃疡作用随着剂量的增加而增强；在 50 和 100μg/kg 剂量下，未观察到溃疡面积。根据这些结果，我们得出结论，抗溃疡机制与α(2)-受体激活之间存在相关性。在给予右美托咪定的大鼠中，除过氧化氢酶（CAT）外，所有抗氧化参数均增加。相反，除髓过氧化物酶（MPO）外，所有氧化应激参数均降低。因此，氧化应激/抗氧化参数在右美托咪定的抗溃疡机制中发挥作用。
