Iloperidone (HP 873) is an atypical antipsychotic agent that is used for treatment of schizophrenia.

5-HT7 receptor (rat):21.6 nM (Ki), D1 receptor (human):216 nM (Ki), D5 receptor (human):319 nM (Ki), D1 receptor (rat):546 nM (Ki), 5-HT2C receptor (human):42.8 nM (Ki), D3 receptor:7.1 nM (Ki), 5-HT6 receptor (rat):42.7 μM (Ki), 5-HT2A receptor (human):5.6 nM (Ki), 5-HT1A receptor (rat):168 nM (Ki), D4 receptor:25 nM (Ki), 5-HT2 receptor (rat):3.1 nM (Ki), D2 receptor (rat):54 nM (Ki)

Iloperidone displays high affinity (Ki < 10 nM) for norepinephrine alpha(1)-adrenoceptors, dopamine D(3) and serotonin 5-HT(2A) receptors. [1] Iloperidone displays higher affinity for the dopamine D3 receptor (Ki = 7.1 nM) than for the dopamine D4 receptor (Ki = 25 nM). Iloperidone displays high affinity for the 5-HT6 and 5-HT7 receptors (Ki = 42.7 nM and 21.6 nM, respectively), and is found to have higher affinity for the 5-HT2A (Ki = 5.6 nM) than for the 5-HT2C receptor (Ki = 42.8 nM). [2] Iloperidone significantly increases dopa accumulation, an index of dopamine turnover in response to D2 receptor blockade, at doses from 0.3 mg/kg to 10 mg/kg i.p. in the striatum and from 1 mg/kg to 10 mg/kg in the nucleus accumbens. [3]

Iloperidone exerts behavioral effects in pharmacological rats models of disrupted sensorimotor gating consistent with "atypical" antipsychotics, mediated by antagonism of dopaminergic and noradrenergic receptors. Iloperidone (1 and 3 mg/kg) prevents the PPI-disruptive effects of treatment with 1 mg/kg PCP. Iloperidone (0.3 mg/kg) prevents cirazoline-induced PPI deficits, independent of its effects on startle magnitude. [4] Iloperidone (10 mg/kg) and Melperone (10 mg/kg) produce an equivalent or a smaller increase in DA release in the nucleus accumbens (NAC) of rats, respectively, compared to the mPFC, whereas none of them increase acetylcholine (ACh) release in the NAC. [5]

Immunoblotting for the mTOR kinase assay: HEK293 cells are plated at 2-2.5×105 cells/well of a 12-well plate and serum-starved for 24 hours in DMEM. Cells are treated with increasing concentrations of Rapamycin (0.05-50 nM) for 15 minutes at 37 °C. Serum is added to a final concentration of 20% for 30 minutes at 37 °C. Cells are lysed, and cell lysates are separated by SDS-PAGE. Resolved proteins are transferred to a polyvinylidene difluoride membrane and immunoblotted with a phosphospecific primary antibody against Thr-389 of p70 S6 kinase. Data are analyzed using ImageQuant and KaleidaGr