Towett Philemon Kipkemoi, Kanui Titus Ikusya, Maloiy Geoffrey Moriaso Ole, Juma Francis, Olongida Ole Miaron Jacob
Neurophysiology and Neuropharmacology Research Laboratory, Department of Veterinary Anatomy, University of Nairobi, P.O. Box 00100-30197, Nairobi, Kenya.
Pharmacol Biochem Behav. 2009 Feb;91(4):566-72. doi: 10.1016/j.pbb.2008.09.011. Epub 2008 Oct 1.
Data available on the role of the opioid systems of the naked mole-rat in nociception is scanty and unique compared to that of other rodents. In the current study, the effect of DAMGO, DPDPE and U-50488 and U-69593 on formalin-induced (20 microl, 10%) nociception were investigated. Nociceptive-like behaviors were quantified by scoring in blocks of 5 min the total amount of time (s) the animal spent scratching/biting the injected paw in the early (0-5 min) and in the late (25-60 min) phase of the test. In both the early and late phases, administration of 1 or 5 mg/kg of DAMGO or DPDPE caused a naloxone-attenuated decrease in the mean scratching/biting time. U-50488 and U-69593 at all the doses tested did not significantly change the mean scratching/biting time in the early phase. However, in the late phase U-50488 or U-69593 at the highest doses tested (1 or 5 mg/kg or 0.025 or 0.05 mg/kg, respectively) caused a statistically significant and naloxone-attenuated decrease in the mean scratching/biting time. The data showed that mu, delta or kappa-selective opioids causes antinociception in the formalin test in this rodent, adding novel information on the role of opioid systems of the animal on pain regulation.
与其他啮齿动物相比，关于裸鼹鼠阿片系统在痛觉感受中作用的数据稀少且独特。在本研究中，研究了DAMGO、DPDPE、U - 50488和U - 69593对福尔马林诱导的（20微升，10%）痛觉感受的影响。通过在测试的早期（0 - 5分钟）和晚期（25 - 60分钟）以5分钟为时间段对动物抓挠/咬注射爪子的总时间（秒）进行评分，来量化类似痛觉感受的行为。在早期和晚期阶段，给予1或5毫克/千克的DAMGO或DPDPE均导致纳洛酮可减弱的平均抓挠/咬时间减少。在所有测试剂量下，U - 50488和U - 69593在早期阶段均未显著改变平均抓挠/咬时间。然而，在晚期阶段，测试的最高剂量（分别为1或5毫克/千克或0.025或0.05毫克/千克）的U - 50488或U - 69593导致平均抓挠/咬时间出现统计学上显著且纳洛酮可减弱的减少。数据表明，μ、δ或κ选择性阿片类药物在该啮齿动物的福尔马林测试中引起抗痛觉作用，为该动物阿片系统在疼痛调节中的作用增添了新信息。
