van Haaren F, De Jongh R, Hoy J B, Karlix J L, Schmidt C J, Tebbett I R, Wielbo D
Department of Psychology, University of Florida, Gainesville 32611-2250, USA.
Pharmacol Biochem Behav. 1999 Feb;62(2):389-94. doi: 10.1016/s0091-3057(98)00184-1.
This experiment was designed to assess the effects of acute and repeated administration of pyridostigmine bromide (a carbamate with prophylactic and therapeutic uses) on response acquisition. Experimentally naïve, male Sprague-Dawley rats were exposed to a situation in which lever presses were either immediately followed by food-pellet presentation or after a 16-s resetting delay. Different groups of rats received either one acute administration of pyridostigmine bromide (10 mg/kg, by gavage) or repeated pyridostigmine administration for 7 days (1.5 mg/kg/day, by gavage). Other groups were treated with distilled water for the same period of time. Both acute and repeated pyridostigmine bromide administration decreased serum cholinesterase levels by approximately 50%, but neither treatment affected brain cholinesterase levels in our assay. Acute and repeated drug administration produced the same behavioral effects. Subjects exposed to the 0-s delay conditions obtained many more food pellets than those exposed to the 16-s delay conditions. Administration of pyridostigmine bromide delayed the onset of responding in some, but not all, of the subjects in the treated groups, independent of the delay condition to which they were exposed. Many more responses were observed on an inoperative lever during the 16-s delay conditions than during the 0-s delay conditions, especially during the 16-s delay condition in which subjects had received acute vehicle administration. Whether or not these effects of small doses of pyridostigmine bromide on response acquisition are of central or peripheral origin will need to be determined in future studies, as response acquisition in the present experiment may have been affected by pyridostigmine's effects on gastrointestinal functioning and/or motor activity.
本实验旨在评估急性和重复给予溴吡斯的明（一种具有预防和治疗用途的氨基甲酸酯）对反应习得的影响。将未经过实验的雄性斯普拉格-道利大鼠置于这样一种情境中：按压杠杆后，要么立即给予食丸，要么经过16秒的重置延迟后给予食丸。不同组的大鼠分别接受一次急性给予溴吡斯的明（10毫克/千克，经口灌胃）或连续7天重复给予溴吡斯的明（1.5毫克/千克/天，经口灌胃）。其他组在相同时间段内用蒸馏水进行处理。急性和重复给予溴吡斯的明均使血清胆碱酯酶水平降低了约50%，但在我们的检测中，这两种处理均未影响脑胆碱酯酶水平。急性和重复给药产生了相同的行为效应。暴露于0秒延迟条件下的实验对象获得的食丸比暴露于16秒延迟条件下的实验对象多得多。给予溴吡斯的明使处理组中的部分（但不是全部）实验对象的反应开始时间延迟，这与它们所暴露的延迟条件无关。在16秒延迟条件下，与0秒延迟条件相比，在无效杠杆上观察到的反应更多，尤其是在接受急性赋形剂给药的实验对象处于16秒延迟条件时。小剂量溴吡斯的明对反应习得的这些影响是源于中枢还是外周，将需要在未来的研究中确定，因为在本实验中，反应习得可能受到了溴吡斯的明对胃肠功能和/或运动活动的影响。
