Table 1. IC₅₀ and I_max values for inhibition of 1 p evoked [DA]_o by the selective D2 receptor agonist quinpirole in non-transgenic (non-Tg), phenotype positive (Phe(+)) and phenotype negative (Phe(−)) mice.

Group	IC₅₀ (nM)	I_max (%)
Non-Tg	46.7 ± 5.3	96.8 ± 1.1
Phe(−)	35.6 ± 6.3	93.0 ± 1.4
Phe(+)	29.7 ± 5.2^*	91.0 ± 2.6

IC₅₀ and I_max values were calculated by fitting a one-component sigmoidal curve to concentration-response data from individual experiments and are expressed as means ± SEM (n = 5 per group). The IC₅₀ for DA release inhibition by quinpirole was significantly lower in Phe (+) mice (p < 0.05 vs. non-Tg) indicating enhanced sensitivity for D2 receptor regulation of DA release. See Methods for experimental details.

Table 1. IC50 and Imax values for inhibition of 1 p evoked [DA]o by the selective D2 receptor agonist quinpirole in non-transgenic (non-Tg), phenotype positive (Phe(+)) and phenotype negative (Phe(−)) mice.

Table 1. IC₅₀ and I_max values for inhibition of 1 p evoked [DA]_o by the selective D2 receptor agonist quinpirole in non-transgenic (non-Tg), phenotype positive (Phe(+)) and phenotype negative (Phe(−)) mice.