Mayorga A J, Carriero D L, Cousins M S, Gianutsos G, Salamone J D
Department of Psychology, University of Connecticut, Storrs 06269-1020, USA.
Pharmacol Biochem Behav. 1997 Feb;56(2):273-9. doi: 10.1016/s0091-3057(96)00225-0.
Previous work has shown that cholinomimetic drugs induce "vacuous" or non-directed jaw movements in rats. In the present study, five experiments were conducted to provide a pharmacological, anatomical and behavioral characterization of tacrine-induced vacuous jaw movements. In the first experiment, tacrine produced vacuous chewing in a dose-related manner in a range of 1.25 mg/kg to 1.0 mg/kg. This effect was reduced, also in a dose-related manner, by the co-administration of the muscarinic antagonist scopolamine in a range of 0.125 to 1.0 mg/kg, but not by N-methylscopolamine. The fourth experiment examined the effect of scopolamine (2.5 to 10.0 micrograms) injected into the ventrolateral striatum on vacuous jaw movements induced by 5.0 mg/kg tacrine. Intrastriatal injections of scopolamine completely blocked tacrine-induced jaw movements. The fifth experiment utilized a slow-motion videotaping system to analyze the temporal characteristics of vacuous chewing induced by 5.0 mg/kg tacrine. The vast majority of the movements occurred in rapid "bursts," and analysis of interresponse times (i.e., the time between each jaw movement) showed that most of the jaw movements occurred within a local frequency range of 3 to 7 Hz. Thus, tacrine-induced jaw movements are reduced by antimuscarinic treatment, and most of these movements occur in the parkinsonian tremor frequency range. Tremulous jaw movements induced by tacrine in rats appear to share some characteristics with Parkinsonian tremor.
先前的研究表明，拟胆碱药物会诱发大鼠出现“空嚼”或无定向的下颌运动。在本研究中，进行了五项实验，以对他克林诱发的空嚼下颌运动进行药理学、解剖学和行为学特征描述。在第一项实验中，他克林在1.25毫克/千克至1.0毫克/千克的剂量范围内以剂量相关的方式产生空嚼行为。毒蕈碱拮抗剂东莨菪碱在0.125至1.0毫克/千克的剂量范围内共同给药时，这种效应也以剂量相关的方式降低，但N - 甲基东莨菪碱则无此作用。第四个实验研究了向腹外侧纹状体注射东莨菪碱（2.5至10.0微克）对5.0毫克/千克他克林诱发的空嚼下颌运动的影响。纹状体内注射东莨菪碱完全阻断了他克林诱发的下颌运动。第五个实验利用慢动作录像系统分析了5.0毫克/千克他克林诱发的空嚼行为的时间特征。绝大多数运动以快速“爆发”的形式出现，对反应间隔时间（即每次下颌运动之间的时间）的分析表明，大多数下颌运动发生在3至7赫兹的局部频率范围内。因此，抗毒蕈碱治疗可减少他克林诱发的下颌运动，且这些运动大多发生在帕金森震颤频率范围内。他克林在大鼠中诱发的震颤性下颌运动似乎与帕金森震颤有一些共同特征。
