Cell experiment:

The functional effects of Amisulpride at the dopamine D3 receptor subtype are assessed. Briefly, the mitogenic response elicited in NG108-15 neuroblastoma-glioma cells stably transfected with human dopamine D3 receptor cDNA by the addition of 10 nM quinpirole in the presence of 1 μM forskolin is quantified by the incorporation of [3H]thymidine. Antagonism of quinpirole-induced mitogenesis is measured in the presence of increasing (0.1 to 100 nM) concentrations of Amisulpride[1].

Animal experiment:

A total of 64 male Swiss albino mice weighing between 20 to 30 g are used. The animals are fed with standard pellet diet and water ad libitum. The mice are divided in different groups (n=8 in each group) and drug administration is done as follows: Group 1 (control): distilled water (1 mL/kg) 23.5, 5 and 1 h before the test. Group 3 (Amisulpride): Amisulpride (70 mg/kg) 23.5, 5 and 1 h before the test[2].

Amisulpride is an atypical antagonist of dopamine D2/D3 receptor with Ki values of 2.8±0.4nM and 3.2±0.3nM for D2 and D3 receptor subtypes, respectively [1].

Amisulpride has shown high affinity to the cloned and stably transfected human dopamine D2 with Ki values of 2.8±0.4nM and 3.2±0.3nM for D2 and D3 receptor subtypes, respectively. Amisulpride has been reported to inhibit radioligand binding to native dopamine D2 receptor in membranes from the rat striatum with an IC50 value of 21nM. Besides, Amisulpride has been revealed to displace [3H]raclopride binding in vivo with an ED50 value of 17.3±1.86mg/kg in the rat limbic system. In addition, Amisulpride has been noted to inhibit quinpirole-induced [3H]thymidine with an IC50 value of 22±3nM [1].

References:
[1] Schoemaker H1, Claustre Y, Fage D, Rouquier L, Chergui K, Curet O, Oblin A, Gonon F, Carter C, Benavides J, Scatton B. Neurochemical characteristics of amisulpride, an atypical dopamine D2/D3 receptor antagonist with both presynaptic and limbic selectivity. J Pharmacol Exp Ther. 1997 Jan;280(1):83-97.