ANTINOCYCEPTIVE EFFECT OF A SYSTEMIC ADMINISTRATION OF PALMITOYLETHANOLAMIDE, STEAROYLETHANOLAMIDE AND DYNCLOFENAC IN RATS WITH EXPERIMENTAL NEUROGENIC PAIN SYNDROME

The antinociceptive effect of palmitoylethanolamide (PEA), stearoyl- ethanolamide (SEA) and sodium diclofenac in experimental peripheral neuropathy in rats was studied. Intraperitoneal administration of PEA one hour prior to stimulation on the 7th and 14th day significantly weakened CCI-induced mechanical hyperalgesia by increasing PNR by 23.1 and 31.8 %, respectively. SEA under similar conditions increased PNR by 27.9 and 30.3 %, while diclofenac – by 29.0 and 26.2 %. New data were obtained and pointed that stearoylethanolamide effectively weakens mechanical hyperalgesia caused by neuropathy. The antinociceptive effects of these fatty acid derivatives in the modeling of neurogenic pain syndrome are comparable to those of sodium diclofenac. It seems advisable to consider PEA and SEA as a basis for drugs, whose addition to treatment regimens of neuropathic pain will increase its effectiveness.

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