Nelson W T, Steiner S S, Brutus M, Farrell R, Ellman S J
Psychopharmacology (Berl). 1981;74(1):58-65. doi: 10.1007/BF00431758.
Pairs of bipolar electrodes were stereotaxically aimed at two of three sites: the locus coeruleus (LC), the substantia nigra, pars compacta (SNC), and the median forebrain bundle (MFB). Rats were shaped to bar-press for trains of intracranial electrical stimulation presented as pairs of monophasic pulses. The first pulse of a pair (the C, conditioning pulse) was followed by a second pulse (the T, test pulse) after a parametrically varied interval. The effects of chronic morphine administration were tested in a paradigm of 7 days saline, 7 days morphine, 1 day morphine+naloxone, and 6 days post-drug saline. High doses of morphine (5 mg/kg) depressed response rates for intracranial self-stimulation (ICSS). LC placements and those just lateral or ventral to the LC showed large increases in ICSS rates under morphine (2.5 mg/kg). This area was delimited on either side by tips that showed response rate depressions under morphine. MFB placements yielded response rate facilitations under morphine. Sites medial to the MFB and ventral within the MFB showed rate depressions under morphine. Dorsal substantia nigra placements showed facilitated rates, whereas placements ventral within the SNC and substantia nigra, pars reticulata (SNR) produced more variable results, with rates tending to be depressed by morphine. The ICSS procedure may be a useful animal model for detecting the abuse potential of drugs.
蓝斑（LC）、黑质致密部（SNC）和中脑前束（MFB）。训练大鼠按压杠杆以获得呈现为双相脉冲对的颅内电刺激序列。一对脉冲中的第一个脉冲（C，条件脉冲）之后，经过参数变化的间隔后跟随第二个脉冲（T，测试脉冲）。在7天生理盐水、7天吗啡、1天吗啡+纳洛酮和6天停药后生理盐水的范式中测试慢性吗啡给药的效果。高剂量吗啡（5mg/kg）降低了颅内自我刺激（ICSS）的反应率。蓝斑部位以及蓝斑外侧或腹侧的部位在吗啡（2.5mg/kg）作用下ICSS率大幅增加。该区域两侧由在吗啡作用下反应率降低的尖端界定。中脑前束部位在吗啡作用下反应率升高。中脑前束内侧和中脑前束腹侧的部位在吗啡作用下反应率降低。黑质背侧部位反应率升高，而黑质致密部腹侧和黑质网状部（SNR）的部位产生的结果更具变异性，吗啡倾向于降低反应率。ICSS程序可能是检测药物滥用潜力的有用动物模型。
