Carroll M E, Meisch R A
Psychopharmacology (Berl). 1981;74(3):197-200. doi: 10.1007/BF00427092.
Changes in oral etonitazene self-administration were compared in four groups of rats that were maintained at 100, 95, 85, or 75% of their pre-experimental free-feeding body weights. Etonitazene (5 micrograms/ml) or water was available for 16 h according to a fixed-ratio (FR) 1 schedule. Each liquid delivery (0.1 ml) was contingent upon a lever-press response. During food deprivation etonitazene intake gradually increased to over two-fold as body weights decreased over 25 sessions; etonitazene intake was inversely proportional to body weight. The 75% weight group showed stereotypy, self-mutilation and large variability in daily etonitazene intake. In another experiment a range of deprivation conditions was studied in a group of six rats with etonitazene (5 micrograms/ml) or water available on an FR 8 schedule during 1-h sessions. When the rats were gradually food satiated, etonitazene-maintained behavior declined but remained higher than water-maintained behavior; however, when they were abruptly food satiated, etonitazene-maintained behavior decreased to low levels.
比较了四组大鼠口服依托尼秦自我给药情况，这四组大鼠分别维持在其实验前自由进食体重的100%、95%、85%或75%。依托尼秦（5微克/毫升）或水按照固定比率（FR）1的时间表供应16小时。每次液体输送（0.1毫升）取决于杠杆按压反应。在食物剥夺期间，随着体重在25个实验阶段中下降，依托尼秦摄入量逐渐增加到两倍以上；依托尼秦摄入量与体重成反比。75%体重组表现出刻板行为、自残行为，且每日依托尼秦摄入量变化很大。在另一项实验中，对一组六只大鼠进行了一系列剥夺条件的研究，在1小时的实验阶段中，依托尼秦（5微克/毫升）或水按照FR 8时间表供应。当大鼠逐渐达到食物饱腹感时，依托尼秦维持的行为下降，但仍高于水维持的行为；然而，当它们突然达到食物饱腹感时，依托尼秦维持的行为降至低水平。
