Antagonism of the 5-HT2 subfamily of receptors and inverse agonism of the 5-HT2C receptor appears to be in part responsible for mirtazapine's efficacy in the treatment of depressive states.[87][88] Mirtazapine increases dopamine release in the prefrontal cortex.[89][90] Accordingly, it was shown that by blocking the α2-adrenergic receptors and 5-HT2C receptors mirtazapine disinhibited dopamine and norepinephrine activity in these areas in rats.[91] In addition, mirtazapine's antagonism of 5-HT2A receptors has beneficial effects on anxiety, sleep and appetite, as well as sexual function regarding the latter receptor.[6][44] Mirtazapine has been shown to lower drug seeking behaviour in various human and animal studies.[92][93][94] It is also being investigated in substance abuse disorders to reduce withdrawal effects and improve remission rates.[92][95][96][97]