Robertson B, Baker G B, Vanderwolf C H
Department of Psychology, University of Western Ontario, London, Canada.
Brain Res. 1991 Aug 2;555(2):265-75. doi: 10.1016/0006-8993(91)90351-u.
The effect of central serotonergic stimulation on hippocampal and neocortical electrical activity and behavior was studied in freely moving rats by administering: (a) tranylcypromine followed by tryptophan, (b) fluoxetine followed by 5-hydroxytryptophan, or (c) p-chloroamphetamine alone. In all rats, scopolamine-resistant hippocampal rhythmical slow activity (RSA), thought to be dependent on brain serotonin, maintained its normal relation to behavior, occurring in close correlation with Type 1 behaviors (postural changes, turning of the head, walking). This RSA was generally absent during stereotyped behavior (head weaving, forepaw treading, hindlimb splaying and tremor). Scopolamine-resistant neocortical low-voltage fast activity (LVFA), also though to be dependent on brain serotonin, was present during Type 1 behaviors and also during stereotyped behavior. Most rats that developed a full stereotyped behavior syndrome had behavioral and electrocortical seizures which were associated with a reduction in the amplitude of hippocampal activity. These seizures were suppressed by methysergide or benserazide. Metergoline (and methysergide to a lesser extent) suppressed the stereotypic behaviors of the serotonin syndrome, resulting in a striking increase in the locomotion caused by central serotonergic stimulation. Such locomotion was accompanied by RSA and LVFA. It was concluded that increased serotonergic activity in the CNS causes an increase in motor activity and a correlated increase in scopolamine-resistant hippocampal RSA and scopolamine-resistant neocortical LVFA and suggested that metergoline blocks serotonin receptors mediating stereotyped behaviors, thereby permitting the expression of serotonin-mediated locomotion.
通过给予以下药物，研究了中枢5-羟色胺能刺激对自由活动大鼠海马和新皮质电活动及行为的影响：(a)反苯环丙胺后给予色氨酸，(b)氟西汀后给予5-羟色氨酸，或(c)单独给予对氯苯丙胺。在所有大鼠中，被认为依赖于脑5-羟色胺的东莨菪碱抵抗性海马节律性慢活动(RSA)，保持其与行为的正常关系，与1型行为(姿势改变、转头、行走)密切相关。这种RSA在刻板行为(头部摆动、前爪踩踏、后肢叉开和震颤)期间通常不存在。同样被认为依赖于脑5-羟色胺的东莨菪碱抵抗性新皮质低电压快活动(LVFA)，在1型行为期间以及刻板行为期间均存在。大多数出现完全刻板行为综合征的大鼠有行为性和皮质电惊厥，这与海马活动幅度的降低有关。这些惊厥被甲基麦角新碱或苄丝肼抑制。麦角乙脲(甲基麦角新碱在较小程度上)抑制5-羟色胺综合征的刻板行为，导致中枢5-羟色胺能刺激引起的运动显著增加。这种运动伴有RSA和LVFA。得出的结论是，中枢神经系统中5-羟色胺能活性增加导致运动活性增加以及东莨菪碱抵抗性海马RSA和东莨菪碱抵抗性新皮质LVFA相应增加，并提示麦角乙脲阻断介导刻板行为的5-羟色胺受体，从而使5-羟色胺介导的运动得以表达。
