Morphological Changes in the Hypothalamic Neurons of Female Rats Exposed to Continuous Illumination

長期持續光照對雌鼠下視丘神經細胞形態的影響

林勇良(Yeong-Liang Lin) ； 戴美雲(Mei-Yun Tai) ； 蔡元奮(Yuan-Feen Tsai)

《The Chinese Journal of Physiology》 33卷3期 (1990/09) Pp. 291-298

摘要

本研究以光學顯微鏡切片觀察接受持續光照11個月，年龄為16-18個月之Long-Evans雌鼠其下視丘神經細胞形態之變化。本研究所觀察的下視丘神經區域包括：室旁核(Paraventricular Nucleus)、視交叉上核(Suprachiasmatic Nucleus)、腹內核(Ventromedial Nucleus)、視前區(Preoptic Area)、視索上核(Supraoptic Nucleus)、和弓狀核(Arcuate Nucleus)等。在上述的下視丘區域內大多數的神經細胞呈現出如下特徵：細胞質密集，Nissl質含量多，並且染色質均匀分布。而這些現象在置放於規則光照週期（光照14小時，黑暗10小時）的對照組雌鼠神經細胞內皆没有發現。由於雌鼠在長期持續光照下所引起體內最明顯的激素變化是松果腺素(Melatonin)含量的降低及雌性素(Estrogen)含量的增加，因此推斷上述神經胞形態的變化可能與此有關。

並列摘要

The morphological changes of neurons in the paraventricular nucleus (PVN), suprachiasmatic nucleus (SCN), ventromedial nucleus (VMN), preoptic area (POA), supraoptic nucleus (SON) and arcuate nucleus (ARN) were studied in 16-18 month-old Long-Evans female rats which had been exposed to continuous illumination (LL) for 11 months. Most neurons in those hypothalamic areas showed compact cytoplasm with abundant Nissl substances and evenly distributed chromatin. These morphological features were not found in the same hypothalamic regions of rats placed under a regular alternative light-dark regimen (14h light and 10h dark). These findings suggest that decreased melatonin and elevated estrogen levels induced by long-term exposure to LL might be involved in the morphological changes in hypothalamic neurons of female rats.

並列關鍵字

continuous illumination ； neuron ； hypothalamus ； morphological changes ； female rats