Microdialysis in vivo Evaluation of the effects of SA-4503, a Sigma1 Receptor Agonist, on the Levels of Monoamines in the Prefrontal Cortex of Conscious Rats

Sigma receptors are widespread in the central nervous system and are differentiated in two subtypes, sigma1 and sigma2. In particular, the sigma1 receptor subtype appears to be able to influence biological mechanisms connected with neuro-degeneration. Furthermore, several studies are implicating sigma1 receptor agonists within antidepressant activity. Evidence of prefrontal cortex abnormalities in clinically depressed subjects have been reported by several works and that monoamines such as serotonin and cathecolamines can be involved in such malfunctions. Up to now the most of the preclinical work performed to analyze the influence of sigma1 receptor agonists upon catecholaminergic and serotoninergic activities in brain areas has been done by means of in vitro as well as ex vivo methodologies. Here, SA-4503, a selective sigma1 receptor agonist with potential antidepressant activity has been tested in vivo upon dopamine (DA), noradrenaline (NA) and serotonin (5-HT) levels detected by micro-dialysis in the medial Prefrontal Cortex (mPFC) of freely moving rats.