https://www.ncbi.nlm...les/PMC2896676/
High secretion of GABA was observed after 60 minutes' contact with NS extract at 25 and 250 μg/mL.
This study pointed that NS possibly facilitates the inhibitory activity of the GABAergic system through a competitive agonist action in the benzodiazepine (BZD) site of the GABA receptor as well as the involvement of dopaminergic and noradrenergic system. The confirmed presence of GABA in the methanolic extract could be directly related to its conduct over the GABA receptor and this could explain the potent sedative and depressive effect on CNS as previously reported.
In conclusion, this study suggests a sedative effect of NS methanolic extract by modification of neurotransmitter amino acids release, because the NS extract may induce an important release of GABA and Gly in the cultured neurons medium and therefore, exert an increase in the agonist action over their receptors.
this study is in vitro, petri dish. thats not even close to rats , let alone humans