Gervais R, Araneda S, Pujol J F
Electroencephalogr Clin Neurophysiol. 1984 May;57(5):462-72. doi: 10.1016/0013-4694(84)90076-2.
This study investigated a possible participation of the centrifugal serotonergic (5-HT) innervation of the olfactory bulb (OB) in the control of the multiunit mitral cell responsiveness in behaving rats. A bilateral injection of 5,6-dihydroxytryptamine solution (5,6-DHT) into the OB induced in this structure an average 70% reduction in the level of endogenous serotonin. Control and treated animals were habituated to eat a single 2 h daily meal. Recording sessions were performed either after a 22 h fasting period or just after the meal. The summated multiunit mitral cell activity and vigilance state parameters were recorded in the absence of and during repeated stimulation by puffs of food odour and isoamyl acetate. The results showed that the 5,6-DHT treatment did not modify significantly previously established centrifugal controls exerted at the OB level: (1) the selective enhancement of the mitral cell responsiveness to food odour occurring in waking food-deprived animals; (2) the inhibition of the olfactory input during slow wave sleep. However, the considered 5-HT projections could mediate some inhibitory influence on mitral cell activity during wakefulness only. Finally, the 5-HT innervation of the OB did not seem to be involved in basic mechanisms of olfactory recognition.
本研究调查了嗅球（OB）的离心性血清素能（5-羟色胺，5-HT）神经支配在行为学实验大鼠中对多单位二尖瓣细胞反应性控制的可能参与情况。向OB双侧注射5,6-二羟基色胺溶液（5,6-DHT）导致该结构内源性血清素水平平均降低70%。将对照动物和处理过的动物驯化至每天只吃一顿2小时的餐食。记录时段在禁食22小时后或餐后立即进行。在不存在食物气味和乙酸异戊酯的反复刺激以及刺激期间，记录多单位二尖瓣细胞活动总和及警觉状态参数。结果显示，5,6-DHT处理并未显著改变先前在OB水平建立的离心控制：（1）清醒且食物匮乏的动物中二尖瓣细胞对食物气味反应性的选择性增强；（2）慢波睡眠期间嗅觉输入的抑制。然而，所考虑的5-HT投射可能仅在清醒期间对二尖瓣细胞活动介导某种抑制性影响。最后，OB的5-HT神经支配似乎未参与嗅觉识别的基本机制。
