Salvinorin A reduces neuropathic nociception in the insular cortex of the rat

Background Neuropathic pain is one of the most important challenges in public health. The search for novel treatments is important for an adequate relief without adverse effects. In this sense salvinorin A (SA), the main diterpene of the medicinal plant Salvia divinorum is an important antinociceptive compound, which acts as a potent agonist of kappa opioid receptor (KOR) and cannabinoid CB1 receptors. Methods We evaluated nociceptive responses in a neuropathic pain model induced by the sciatic nerve ligature (SNL) in the right hind paw, after the microinjection of SA, Salvinorin B (SB), KOR and CB1 antagonists directly in the insular cortex (IC) in male wistar rats. Results We found a potent antinociceptive effect with the administration of SA. Moreover, this effect was blocked by the administration of a KOR antagonist as well as the administration of a CB1 antagonist. Conclusion Salvinorin A has a potent antinociceptive effect when is administered centrally in the IC by the interaction with KOR and CB1 receptors. Significance We show evidence on the effectiveness of the administration of salvinorin A in the IC in a rodent model of neuropathic pain. These results support the use of novel compounds like SA as a therapeutic alternative for neuropathic pain relief.