RESUMO
OBJECTIVE: To study the effect of ethylmethylhydroxypyridine succinate (EMHPS) on the analgesic effect of the non-selective cyclooxygenase (COX) inhibitor diclofenac sodium and the selective COX-2 inhibitor etoricoxib in models of acute visceral and somatic pain and to evaluate the possibility of using EMHPS in combination with COX inhibitors to reduce their doses while maintaining analgesic efficiency. MATERIAL AND METHODS: We studied the effect of EMHPS with a single oral administration on the analgesic effects of non-steroidal anti-inflammatory drugs (NSAIDs): the non-selective COX inhibitor diclofenac sodium and the selective COX-2 inhibitor etoricoxib - on models of acute visceral (vinegar writhing test) and somatic pain (formalin test and mechanical hyperalgesia during inflammation) in an experiment on mice and rats. RESULTS: In a model of acute visceral pain in mice, EMGPS (25-100 mg/kg) does not have a significant effect on its severity, but enhances the analgesic effect of diclofenac sodium (0.5 mg/kg) and etoricoxib (1 mg/kg). In the formalin test in rats, which simulates pain during surgical incisions (trauma), EMGPS (25 mg/kg) increases the severity of the analgesic effect of COX inhibitors (1 mg/kg), primarily by reducing pain in the acute phase caused by the effect of formalin on afferent neurons. In a model of mechanical hyperalgesia in rats caused by exudative inflammation after injection of a carrageenan solution into the paw, EMHPS enhances the effect of diclofenac to a greater extent than etoricoxib. CONCLUSION: The data obtained indicate the feasibility of a clinical study of the use of EMGPS in combination with NSAIDs for visceral and somatic pain in order to assess its ability to increase the therapeutic effect of NSAIDs.
