the effects of quinpirole and sulpiride on conflict responses in rat

in this investigation wer studied the effect of dopaminergic system on the conflict behavior in rat, using vogel’s test. the related drugs were injected intraperitonealy (ip), and produced the following results:diazepam at doses of 0.5 and 1 mg/kg increased the lick –shock responses in the vogel’s thest. quinpirole (d2-agnosit), at doses of 0.1 and 10 mg/kg, increased the confict responses, wheraes suplpirde (d2 antagonist) did not affect them.apomorphine (d1 and d2 agonist) had a biphasic effect on the conflict responses. this drug decreased the number of shoks at low dose (0.01 mg/kg) while increased them at high dose (1 mg/kg). haloperidol at dose of 1 mg/kg reduced the conflit responses significantly. administration of both sulpiride (30 mg/kg) and quinpirole (10 mg/kg) together, increase the confict responses.these results suggest that d2-receptor agonist drugs may exert anixolytic and d2-receptor antagonists may produce anxiogenic effects in rat.