Induction of abnormal movements and postures by systemic oxotremorine in Gnal+/− mice. A, Schedule of behavioral monitoring of oxotremorine injections. Behavior was scored after 20 min to avoid interference with the initial predominant peripheral muscarinic effects. B, Examples of abnormal postures found in Gnal+/− mice 20 min after oxotremorine treatment (0.1 mg/kg). The red arrows indicate abnormal positions of paws. C, Time course of abnormal motor scores after oxotremorine treatment (0.1 mg/kg) in Gnal+/− and Gnal+/+ mice in 2 different experiments rated by 1 (Experiment 1) or 2 (Experiment 2) evaluators blind to the genotype. Motor defects were scored (Table 2) in 10 min intervals and plotted for the end time point. Top, Experiment 1, n = 9 animals per group, two-way ANOVA: time, F(3,57) = 5.04, p < 0.01; genotype, F(1,19) = 13.54, p < 0.01; interaction, F(3,56) = 0.7, p = 0.5. Bottom, Experiment 2, n = 12 animals per group, scores are the mean of the 2 evaluations, two-way ANOVA: time, F(3,33) = 16.82, p < 0.0001; genotype, F(1,11) = 4.97, p < 0.05; interaction, F(3,33) = 1.58, p = 0.2. D, Absence of epileptiform activity in the motor cortex of Gnal+/− mice treated with oxotremorine (0.1 mg/kg). Examples of EEG recording before oxotremorine administration (baseline, top) and during a phase of abnormal posture induced by oxotremorine (bottom). E, Abnormal movement scores during 10 min in the absence of any treatment. Two-tailed t test, t = 1.13, p = 0.3. F, Effects of THX (1 or 20 mg/kg as indicated) pretreatment on oxotremorine (Oxo)-induced responses. Motor scores were measured on four consecutive 10 min intervals and their mean plotted. Two-way ANOVA: treatment, F(3,65) = 13.9, p < 0.0001; genotype, F(1,65) = 12.9, p < 0.001; interaction, F(3,65) = 2.2, p = 0.1. Data are shown as means ± SEM. Sidak's multiple-comparisons test: Gnal+/− versus Gnal+/+; ***p < 0.001; Oxo versus Oxo+THX, #p < 0.05, ###p < 0.001. G, Effects of the nicotinic antagonist, mecamylamine (Meca; 3 mg/kg) and the M1 preferential antagonists telenzepine (Telen, 3 mg/kg) and pirenzepine (Piren, 10 mg/kg) on Oxo-induced responses in Gnal+/− and Gnal+/+ mice. Motor scores were measured and plotted as in F. Two-way ANOVA: treatment, F(5,129) = 158.7, p < 0.0001; genotype, F(1,129) = 11.45, p < 0.001; interaction, F(5,129) = 3.2, p < 0.05. Data are shown as means ± SEM. Sidak's multiple-comparisons test after two-way ANOVA: Gnal+/− versus Gnal+/+; **p < 0.01; **p < 0.01; Oxo (0.1 mg/kg) versus other treatments, ###p < 0.001. Data for Oxo 0.1 mg/kg alone in F and G are those of Experiments 1 and 2 in C, respectively.