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

Abstract

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.