Posted by phidippus on September 4, 2012, at 15:41:02
In reply to Re: Nuvigil / Provigil Effects » phidippus, posted by SLS on September 3, 2012, at 23:05:23
Provigil and Nuvigil are both based on the drug Modafanil, so have similar modes of action.
Modafinil induces wakefulness in part by its action in the anterior hypothalamus. Its dopamine-releasing action in the nucleus accumbens is weak and dose-dependent.
Modafinil has central alpha 1-adrenergic agonist effects i.e. it directly stimulates the receptors. Modafinil also inhibits the reuptake of noradrenaline by the noradrenergic terminals on sleep-promoting neurons of ventrolateral preoptic nucleus (VLPO). More significant, perhaps, is its ability to increase excitatory glutamatergic transmission. This reduces local GABAergic transmission, thereby diminishing GABA(A) receptor signalling on the mesolimbic dopamine terminals.
Orexin neurons are activated by modafinil. Orexinergic neurons are found exclusively in the lateral hypothalamic area. Their activation is associated with enhanced pleasure-seeking and motivation as well as arousal. Orexinergic fibers project to the entire central nervous system.
Eric
poster:phidippus
thread:1024632
URL: http://www.dr-bob.org/babble/20120830/msgs/1024877.html