Tomić, Maja A. (7006939166)Maja A. (7006939166)TomićVučković, Sonja M. (7003869333)Sonja M. (7003869333)VučkovićStepanović-Petrović, Radica M. (6506683297)Radica M. (6506683297)Stepanović-PetrovićUgrešić, Nenad D. (6602152735)Nenad D. (6602152735)UgrešićParanos, Sonja Lj (23095235600)Sonja Lj (23095235600)ParanosProstran, Milica Š. (7004009031)Milica Š. (7004009031)ProstranBošković, Bogdan (7004055023)Bogdan (7004055023)Bošković2025-06-132025-06-132007https://doi.org/10.1213/01.ane.0000287270.35176.3ehttps://www.scopus.com/inward/record.uri?eid=2-s2.0-37349011809&doi=10.1213%2f01.ane.0000287270.35176.3e&partnerID=40&md5=06a194661eedf9c6478ca6690479812bhttps://remedy.med.bg.ac.rs/handle/123456789/10925BACKGROUND: We studied whether peripheral α2-adrenergic receptors are involved in the antihyperalgesic effects of oxcarbazepine by examining the effects of yohimbine (selective α2-adrenoceptor antagonist), BRL 44408 (selective α2A-adrenoceptor antagonist), MK-912 (selective α2C-adrenoceptor antagonist), and clonidine (α2-adrenoceptor agonist) on the antihyperalgesic effect of oxcarbazepine in the rat model of inflammatory pain. METHODS: Rats were intraplantarly (i.pl.) injected with the proinflammatory compound concanavalin A (Con A). A paw-pressure test was used to determine: 1) the development of hyperalgesia induced by Con A; 2) the effects of oxcarbazepine (i.pl.) on Con A-induced hyperalgesia; and 3) the effects of i.pl. yohimbine, BRL 44408, MK-912 and clonidine on the oxcarbazepine antihyperalgesia. RESULTS: Both oxcarbazepine (1000-3000 nmol/paw; i.pl.) and clonidine (1.9-7.5 nmol/paw; i.pl.) produced a significant dose-dependent reduction of the paw inflammatory hyperalgesia induced by Con A. Yohimbine (260 and 520 nmol/paw; i.pl.), BRL 44408 (100 and 200 nmol/paw; i.pl.) and MK-912 (10 and 20 nmol/paw; i.pl.) significantly depressed the antihyperalgesic effects of oxcarbazepine (2000 nmol/paw; i.pl.) in a dose-dependent manner. The effects of antagonists were due to local effects since they were not observed after administration into the contralateral hindpaw. Oxcarbazepine and clonidine administered jointly in fixed-dose fractions of the ED50 (1/4, 1/2, and 3/4) caused significant and dose-dependent reduction of hyperalgesia induced by Con A. Isobolographic analysis revealed an additive antihyperalgesic effect. CONCLUSIONS: Our results indicate that the peripheral α2A and α2C adrenoceptors could be involved in the antihyperalgesic effects of oxcarbazepine in a rat model of inflammatory hyperalgesia. © 2007 by International Anesthesia Research Society.