Article Figures & Data
Figures
- Fig. 1.
Total horizontal motor activity after intraperitoneal administration of caffeine in habituated rats. The results represent means ± SEM of the accumulated motor activity counts during the first 60 min period of observation (n = 6 per group). Significant motor activation was obtained with caffeine in a dose of 10 mg/kg (CAFF 10) and caffeine in a dose of 30 mg/kg (CAFF 30). **p < 0.01 compared with the group treated with saline (SAL).CAFF 3 and CAFF 100indicate 3 and 100 mg/kg caffeine, respectively.
- Fig. 2.
Extracellular concentrations of dopamine (DA) and glutamate (Glu) in the shell of the NAc after intraperitoneal administration of saline or caffeine [3 (caff 3), 10 (caff 10), 30 (caff 30), or 100 (caff 100) mg/kg]. The results represent means ± SEM of the percentage of basal values of the extracellular concentrations of dopamine and glutamate (n = 6–8 per group). Basal values were the means of three values before drug administration. Caffeine at doses of 10 and 30 mg/kg but not at doses of 3 and 100 mg/kg significantly increased the extracellular levels of dopamine and glutamate (Student's pairedt test; only significant results of pretreatment vs post-treatment are shown).
- Fig. 3.
Extracellular concentrations of dopamine (DA) and glutamate (Glu) in the shell and core of the NAc after intraperitoneal administration of caffeine [30 mg/kg (caff 30)]. The results represent means ± SEM of the percentage of basal values of the extracellular concentrations of dopamine and glutamate (n = 6–8 per group). Basal values were the means of three values before drug administration. Caffeine (30 mg/kg) produced a significant increase in the extracellular concentration of dopamine, but not of glutamate, in the core of the NAc (Student's paired t test; only significant results of pretreatment vs post-treatment are shown). This effect was significantly different from that produced by 30 mg/kg caffeine in the shell of the NAc (interaction between area and treatment factors: p < 0.01 by repeated-measures ANOVA).
- Fig. 4.
Extracellular concentrations of dopamine (DA) and glutamate (Glu) in the shell of the NAc after intraperitoneal administration of the adenosine A1 receptor antagonist CPT (4.8 mg/kg) and the A2A receptor antagonist SCH 58261 (2 mg/kg). The results represent means ± SEM of the percentage of basal values of the extracellular concentrations of dopamine and glutamate (n = 6–7 per group). Basal values were the means of three values before drug administration. CPT but not SCH 58261 produced a significant increase in the extracellular concentrations of dopamine and glutamate (Student's pairedt test; only significant results of pretreatment vs post-treatment are shown).
