Systemic quinpirole enhances tramadol analgesia in inflammatory pain, but not in neuropathic pain in male rats.

Pain is a morbidity or comorbidity with a high incidence that significantly impacts the well-being of patients. In this study, we evaluated the effects of systemic administration of tramadol, a weak mu-opioid receptor (MOR) agonist, plus quinpirole (a D2-like receptor agonist). The study was performed in naïve rats and in rats with induced inflammatory and neuropathic pain.

The Role of the Insular Cortex and Serotonergic System in the Modulation of Long-Lasting Nociception.

The insular cortex (IC) is a brain region that both receives relevant sensory information and is responsible for emotional and cognitive processes, allowing the perception of sensory information. The IC has connections with multiple sites of the pain matrix, including cortico-cortical interactions with the anterior cingulate cortex (ACC) and top-down connections with sites of descending pain inhibition. We explored the changes in the extracellular release of serotonin (5HT) and its major metabolite, 5-hydroxyindoleacetic acid (5HIAA), after inflammation was induced by carrageenan injection.

Causal computations of supplementary motor area on spatial impulsivity.

Spatial proximity to important stimuli often induces impulsive behaviour. How we overcome impulsive tendencies is what determines behaviour to be adaptive. Here, we used virtual reality to investigate whether the spatial proximity of stimuli is causally related to the supplementary motor area (SMA) functions.