Loxapine Succinate

In the presence of Loxapine, [³H]ketanserin binds to 5-HT₂ receptor in Frontal cortex of brain in human and bovine with ki value of 6.2 nM and 6.6 nM, respectively. Loxapine has the rank order of potency for the various receptors appears to be as follows:5-HT2≥D4>>>D1>D2 in comparing competition experiments involving the human membranes. ^[1] Loxapine 0.2 μM, 2 μM and 20 μM reduces IL-1beta secretion by LPS-activated mixed glia cultures after 1 and 3 days of exposure. Loxapine in concentrations of 0.2 μM, 2 μM and 20 μM reduces IL-2 secretion in mixed glia cultures after 1 and 3 days of exposure, and additionally Loxapine decreases IL-1beta and IL-2 secretion in LPS-induced microglia cultures in concentrations of 2 μM, 10 μM and 20 μM. ^[2]

Loxapine (5 mg/kg) induces a very significant reduction (more than 50%) of serotonin (S₂) receptor density after 4 weeks or 10 weeks of daily injection in the rat. Loxapine (5 mg/kg) does not change dopamine receptor density but greatly reduces serotonin receptor density by 47% in the brain of rats. ^[3] Loxapine (0.3 mg/kg s.c.) induces marked catalepsy, the scores reaching the cut-off level of 45 s two to 5 hours after injection in rats. Loxapine-induced catalepsy is fully established then treated by clozapine (10 mg/kg s.c.), the high catalepsy score is reduced to a value not significantly different from vehicle-treated controls in rats. ^[4]