Efeito antinociceptivo da riparina IV em modelos animais: mecanismos de ação envolvidos

• Ano de defesa: 2017
• Autor(a) principal: Dias, Marília Leite
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Nociceptividade; Dor; Carragenina
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/44078

From the green fruit of Aniba riparia (Nees) Mez, some alcamides with interesting therapeutic potential, named Riparinas, are found. Through a process of chemical modification, a structural analogue of these substances, Riparina IV, was synthesized. Previous studies have shown that it has anxiolytic and antidepressant effects, as well as antinociceptive effect. The present work was developed with the approval of CEUA / UFC (nº 06/16), with the objective of evaluating the role of Rip.IV in the process of nociception and the pharmacological mechanisms related to its activity. Initially, male Swiss mice were used and experimental models of nociception were performed: acetic acid induced contortions, mechanical hypernociception induced by algic agents (PGE2 and epinephrine), nociception test induced by intraplantar injection of capsaicin, cinnamaldehyde, menthol, acidic saline, PMA And 8-Br-cAMP. In addition to the behavioral tests, the effect of Rip.IV on the Composite Action Potential (PAC) on the sciatic nerve of Wistar rats was analyzed. We performed a time curve with Rip.IV at a dose of 50mg / kg in the test of abdominal contortions induced by acetic acid, where it was observed that the effects of Rip.IV appeared after 30 minutes and persisted up to 240 minutes. Rip.IV (25 and 50 mg / kg, v.o.) was able to significantly reduce carragennan and PGE2-induced hypernociception, but did not present a statistically significant effect on the test performed with epinephrine. In the investigation of the antinociceptive mechanism, it was observed that Rip.IV demonstrated a PKA-related effect, as well as with ion channels related to this pathway. Rip IV blocked the positive amplitude of 1st and 2nd CAP in a concentration-dependent way, and these effects were reversible after washout. Both components reduced the conduction velocity of CAP similarly. The results demonstrate that Rip IV presents an antinociceptive effect related to inhibition of electric activity of peripheral nervous system.