Synchronizing mechanism of suprachiasmatic cells

视交叉上细胞的同步机制

• 批准号: 13670070
• 负责人: WATANABE Kazuto
• 金额: $ 2.18万
• 依托单位: Dokkyo Medical University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13670070/
• 关键词: Circadian rhythm; Suprachiasmatic; Vasopressin; cell culture; period; Synchronization; 培養; GABA; 自由継続周期; 興奮性アミノ酸; VIP

In mammals, circadian rhythms are driven by a pacemaker located in the suprachiasmatic nuclei (SCN) of the hypothalamus. The pacemaker is composed of an ensemble of multiple, single-cell oscillators in the SCN. The isolated rat suprachiasmatic cells cultured in vitro express circadian oscillation of vasopressin (AVP) release for weeks. The amplitude of the rhythm was higher in the cultures plated at high density. The large amplitude of the rhythm indicates the individual rhythms in the dissociated AVP-releasing cells are synchronized to each other. Synchronization was observed between groups of the cells. When two groups of the cells with different phase were co-cultured, the phase of one group was synchronized to another one. The cell-to-cell contact was not necessarily required for this synchronization.Since GABA has been postulated as a coupling agent for the SCN cells, we examined the effect of GABA on the rhythm of AVP release. When GABA was added to the culture medium, AVP releas … More e from the cells was markedly reduced. The GABA-induced inhibition occurred at all phases of the circadian cycle. While GABA disturbed. the circadian oscillation of AVP release) it was gradually restored. After the recovery of the rhythm, slight phase-shift was observed. Magnitude and direction of the shift depended on timing of the application, maximum phase delay at the beginning of subjective day, and the maximum phase advance at the beginning of subjective night. Bicuculline, a GABA-A antagonist, increased AVP release, but did not inhibit the synchronization among the AVP cells even under long-term application.The SCN slice culture showed circadian oscillation of AVP release with a period length (±S.E..M) of 23.84±0.03 h. This period is very similar to the one we previously reported in dispersed SCN cultures and is also close to that of behavioral rhythms. When the ventral part was removed by surgical cut across the slice in the horizontal plane, however, the period became shorter (23.22 h± 0.08 h). On the other hand, the removal of the dorsal part did not affect period length. These results suggest that the oscillators in ventral and dorsal cells contribute differently to period length and that the dorsal oscillators are regulated by ventral one to form a single integrated oscillator. Less

在哺乳动物中，昼夜节律是由位于下丘脑视交叉上核(SCN)的起搏器驱动的。起搏器由SCN中的多个单细胞振荡器组成。体外培养的大鼠视交叉上皮细胞表现出持续数周的加压素(AVP)释放的昼夜振荡。在高密度培养中，节律的幅度较高。节律的大幅度表明，分离的AVP释放细胞中的个体节律是相互同步的。观察到细胞组之间的同步性。当两组不同时相的细胞共培养时，一组细胞的时相与另一组细胞同步。由于GABA被认为是SCN细胞的偶联剂，我们研究了GABA对AVP释放节律的影响。当加入γ-氨基丁酸时，血管加压素释放…来自细胞的更多的E明显减少。GABA诱导的抑制作用发生在昼夜节律的所有阶段。而GABA则受到干扰。AVP释放的昼夜节律)逐渐恢复。恢复节律后，观察到轻微的相移。移位的大小和方向取决于应用的时机、主观白天开始时的最大相位延迟以及主观夜晚开始时的最大相位推进。GABA-A拮抗剂荷包牡丹碱可促进AVP的释放，但不抑制AVP细胞之间的同步性。SCN切片培养显示AVP释放的昼夜节律振荡，周期长度(±S.E.M)为23.84±0.03h，这一周期与我们在分散的SCN培养中报道的周期非常相似，也接近于行为节律。而横切横切面切除腹侧部的时间缩短(23.22h±0.08h)。另一方面，去掉背部并不影响周期长度。这些结果表明，腹侧和背侧细胞中的振荡器对周期长度的贡献不同，背侧振荡器受腹侧振荡器的调节，形成单一的集成振荡器。较少

项目成果

篠原一之, 渡辺和人, 山岡貞夫: "培養視交叉上核神経細胞の概日リズム"神経研究の進歩. 45. 783-789 (2001)

Kazuyuki Shinohara、Kazuto Watanabe、Sadao Yamaoka：“培养的视交叉上核神经元的昼夜节律”神经学研究进展 45. 783-789 (2001)。

Svobodova, I., Vanecek, J., Zemkova, H.: "The bidirectional phase-shifting effects of melatonin on the arginine vasopressin secretion rhythm in rat suprachiasmatic nuclei in vitro."Molecular Brain Research. 116. 80-85 (2003)

Svobodova, I.、Vanecek, J.、Zemkova, H.：“褪黑激素对体外大鼠视交叉上核精氨酸加压素分泌节律的双向相移作用。”分子脑研究。

Svobodova, I., Vanecek, J., Zemkova, H.: "The bidirectional phase-shifting effects of melatonin on the arginine vasopressin secretion rhythm in rat suprachiasmatic nuclei in vitro."Molecular Brain Research. 116(1-2). 80-85 (2003)

Svobodova, I.、Vanecek, J.、Zemkova, H.：“褪黑激素对体外大鼠视交叉上核精氨酸加压素分泌节律的双向相移作用。”分子脑研究。

Watanabe, K., Deboer, T., Meijer, J.H.: "Light-induced resetting of the circadian pacemaker : Quantitative analysis of transient versus steady-state phase shifts."J.Biol.Rhythm. 16. 564-573 (2001)

Watanabe, K.、Deboer, T.、Meijer, J.H.：“光诱导的昼夜节律起搏器重置：瞬态相移与稳态相移的定量分析。”J.Biol.Rhythm。

Watanabe, K., Deboer, T., Meijer, J.H.: "Light-induced resetting of the circadian pacemaker : Quantitative analysis of transient versus steady-state phase shifts"J. Biol. Rhythm. 16(6). 564-573 (2001)

Watanabe, K.、Deboer, T.、Meijer, J.H.：“光诱导的昼夜节律起搏器重置：瞬态相移与稳态相移的定量分析”J.