Stimulating muscarinic M1 receptors in the anterior cingulate cortex reduces mechanical hypersensitivity via GABAergic transmission in nerve injury rats.

Stimulating muscarinic M1 receptors in the anterior cingulate cortex reduces mechanical hypersensitivity via GABAergic transmission in nerve injury rats.
Brain Res. 2018 Oct 16;:
Authors: Koga K, Matsuzaki Y, Migita K, Shimoyama S, Eto F, Nakagawa T, Matsumoto T, Terada K, Mishima K, Furue H, Honda K
Abstract
Cholinergic systems modulate synaptic transmission across the neuraxis and play an important role in higher brain function including cognition, arousal and nociception. The anterior cingulate cortex (ACC) is a fundamental brain region for nociception and chronic pain, and receives cholinergic projections mainly from basal forebrain. Recently, we found that the activation of muscarinic M1 receptors in the ACC produced antinociceptive behavior in response to mechanical stimulation. However, it has not been tested whether stimulating muscarinic receptors in the ACC can reduce mechanical hypersensitivity in animal models of chronic pain. Here, we tested whether the activation of muscarinic M1 receptors in the ACC can alleviate mechanical hypersensitivity in a nerve injury model. The activation of muscarinic M1/M4 receptors by McN-A-343 injected into the contralateral side of the ACC, but not into the ventral posterolateral nucleus, was found to dose-dependently reduce mechanical hypersensitivity 7 days following partial sciatic nerve ligation in rats. The reduction of mechanical hypersensitivity by McN-A-343, was blocked by a select...

Source: Brain Research - October 16, 2018 Category: Neurology Authors: Koga K, Matsuzaki Y, Migita K, Shimoyama S, Eto F, Nakagawa T, Matsumoto T, Terada K, Mishima K, Furue H, Honda K Tags: Brain Res Source Type: research