Price M T, Murray G N, Fibiger H C
Pharmacol Biochem Behav. 1977 Jan;6(1):11-5. doi: 10.1016/0091-3057(77)90153-8.
The present experiments examined the role of the dorsal tegmental noradrenergic bundle (DTNB) in operant responding for food under various schedules of reinforcement. This catecholaminergic neuronal system originates in the nucleus locus coeruleus and has diffuse projections to hippocampus and cerebral cortex. Bilateral stereotaxic injections of 6-hydroxydopamine into the DTNB of rats reduced hippocampal-cortical noradrenaline to less than 5% of control levels. Animals with these lesions acquired a continuously reinforced (CRF) bar-press response at the same rate as controls. Compared to controls rats with DTNB lesions responded at significantly lower rates on a variable interval 30 (VI 30) schedule. Extinction after VI 30 responding did not differ significantly between control and lesioned animals. In another experiment no significant difference was observed between DTNB lesioned and control groups on the rate of responding on a fixed ratio 30 (FR 30) schedule. The results are discussed with reference to previous reports indicating changes in operant responding after intraventricular injections of 6-hydroxydopamine. The data failed to support the hypothesis that the DTNB is critically involved in learning and memory.
本实验研究了背侧被盖去甲肾上腺素能束（DTNB）在不同强化程序下对食物的操作性反应中的作用。这个儿茶酚胺能神经元系统起源于蓝斑核，并广泛投射到海马体和大脑皮层。对大鼠的DTNB进行双侧立体定位注射6-羟基多巴胺，可使海马-皮层去甲肾上腺素水平降低至对照水平的5%以下。有这些损伤的动物以与对照相同的速率获得了连续强化（CRF）压杆反应。与对照相比，DTNB损伤的大鼠在可变间隔30（VI 30）程序上的反应速率显著更低。在VI 30反应后的消退在对照动物和损伤动物之间没有显著差异。在另一个实验中，DTNB损伤组和对照组在固定比率30（FR 30）程序上的反应速率没有观察到显著差异。结合之前关于脑室内注射6-羟基多巴胺后操作性反应变化的报告对结果进行了讨论。数据未能支持DTNB关键参与学习和记忆的假设。
