Lee R S, Strahlendorf H K, Strahlendorf J C
Brain Res. 1985 Feb 18;327(1-2):249-58. doi: 10.1016/0006-8993(85)91518-5.
Electrophysiological aspects of thiamine depletion in the rat induced by dietary deficiency are described. Behavioral changes as well as qualitative and quantitative alterations in the sensitivity of cerebellar Purkinje cells to iontophoretically-applied 5-hydroxytryptamine (5-HT) were observed. Thiamine-deficient rats were characterized essentially by ataxia, piloerection, paresis, apparent weakness, and hypothermia after 4-6 weeks on a thiamine-free diet. Basal Purkinje cell firing frequency was unaffected by thiamine deficiency. The response of Purkinje cells to iontophoretically-applied 5-HT was solely inhibitory in deficient rats. In control rats, however, responses to 5-HT were excitatory, biphasic, or inhibitory. Neurons in the thiamine-deficient animals were more sensitive to the inhibitory effects of 5-HT, as demonstrated by a significant parallel shift to the left of the dose-response curve. Durations of 5-HT effects were similar in both groups. Dose-response relationships for GABA-induced inhibition of Purkinje cell firing from thiamine deficient and control rats did not differ from one another. These data demonstrate a relatively selective effect of thiamine depletion on cerebellar serotonergic neurotransmission assessed electrophysiologically. We believe there is up-regulation of 5-HT receptors on Purkinje cells caused by thiamine deficiency-induced impairment of indoleamine input to the cerebellum from raphe and related nuclei.
描述了饮食缺乏诱导的大鼠硫胺素缺乏的电生理方面。观察到行为变化以及小脑浦肯野细胞对离子电泳施加的5-羟色胺（5-HT）敏感性的定性和定量改变。硫胺素缺乏的大鼠在无硫胺素饮食4-6周后主要表现为共济失调、竖毛、轻瘫、明显虚弱和体温过低。基础浦肯野细胞放电频率不受硫胺素缺乏的影响。在缺乏硫胺素的大鼠中，浦肯野细胞对离子电泳施加的5-HT的反应仅为抑制性。然而，在对照大鼠中，对5-HT的反应是兴奋性、双相性或抑制性的。硫胺素缺乏动物的神经元对5-HT的抑制作用更敏感，剂量反应曲线明显向左平行移动证明了这一点。两组中5-HT作用的持续时间相似。硫胺素缺乏和对照大鼠中GABA诱导的浦肯野细胞放电抑制的剂量反应关系彼此无差异。这些数据证明了硫胺素缺乏对通过电生理评估的小脑5-羟色胺能神经传递具有相对选择性的作用。我们认为，硫胺素缺乏引起的从缝际核和相关核向小脑的吲哚胺输入受损导致浦肯野细胞上5-HT受体上调。
