Figure 9.

Effects of intra-BLA D1 or D2 receptor blockade on NAshell neuronal response patterns to morphine administration. A, Group neuronal recording data from NAshell population samples showing the effects of intra-BLA SCH 23390 (1.0 μg/0.5 μl) on neuronal responses to morphine (1.0 mg/kg, i.v.) administration. Whereas intra-BLA D1 receptor blockade blocks excitatory responses to morphine administration in opiate-naive rats, the same treatment does not block NAshell neuronal responses to morphine in rats recorded in the opiate-dependent/withdrawn state. B, Neuronal recording data from NAshell population samples showing the effects of intra-BLA eticlopride (1.0 μg/0.5 μl) on neuronal activity following morphine (1.0 mg/kg, i.v.) administration. Whereas intra-BLA D2 receptor blockade has no effects on excitatory NAshell neuronal responses to morphine in rats recorded in the opiate-naive state, the same treatment completely blocked NAshell neuronal responses to morphine in rats recorded in the opiate-dependent/withdrawn state. C, Sample NAshell neuronal recording rastergram showing the effects of intra-BLA SCH 23390 on neuronal activity after morphine administration in an opiate-naive rat. D, Sample NAshell neuronal recording rastergram showing the effects of intra-BLA SCH 23390 on neuronal activity after morphine administration in an opiate-dependent/withdrawn rat. E, Sample NAshell neuronal recording rastergram showing the effects of intra-BLA eticlopride on neuronal activity after morphine administration in an opiate-naive rat. F, Sample NAshell neuronal recording rastergram showing the effects of intra-BLA SCH eticlopride on neuronal responding to morphine administration in an opiate-dependent/withdrawn rat. G, Summary of NAshell neuronal group responses to morphine administration expressed as percentage change from baseline across saline control groups, intra-BLA SCH 23390 experimental groups, and intra-BLA eticlopride experimental groups.