Inatomi T
Department of Ophthalmology, Kyoto Prefectural University of Medicine, Japan.
Nippon Ganka Gakkai Zasshi. 1994 Aug;98(8):749-59.
We investigated the distribution, diurnal variation, and time of expression of aromatic L-amino acid decarboxylase (AADC), a second-step enzyme of the monoamine synthetic pathway, in the rat suprachiasmatic nucleus (SCN), by immunocytochemistry and in situ hybridization. AADC immunoreactive and mRNA expressing cells were observed in the dorsomedial and dorsolateral portions of the SCN. Double labeling immunofluorescence demonstrated that about 70% of AADC neuron in the dorsomedial portion contained vasopressin immunoreactivity. AADC mRNA expression in the SCN showed day-night variation, with higher signals in the daytime than at night. Developmental study demonstrated that AADC immunoreactivity and mRNA in the SCN were expressed at embryonic day 18, the onset time for fetal circadian rhythm. These findings suggest that AADC neurons in the SCN may play some role in the generation and entrainment of circadian rhythm.
我们通过免疫细胞化学和原位杂交技术，研究了单胺合成途径中的第二步酶——芳香族L-氨基酸脱羧酶（AADC）在大鼠视交叉上核（SCN）中的分布、昼夜变化及表达时间。在SCN的背内侧和背外侧部分观察到了AADC免疫反应性和mRNA表达细胞。双重标记免疫荧光显示，背内侧部分约70%的AADC神经元含有加压素免疫反应性。SCN中AADC mRNA表达呈现昼夜变化，白天的信号高于夜间。发育研究表明，SCN中的AADC免疫反应性和mRNA在胚胎第18天表达，这是胎儿昼夜节律的起始时间。这些发现表明，SCN中的AADC神经元可能在昼夜节律的产生和同步中发挥一定作用。
