Laboratory of Neuroendocrinology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan.
Neurosci Res. 2012 Jan;72(1):16-22. doi: 10.1016/j.neures.2011.09.008. Epub 2011 Oct 1.
The pineal gland secretes melatonin under circadian control via nocturnal noradrenergic stimulation, and expresses vesicular glutamate transporter (VGLUT) 1, VGLUT2 and a VGLUT1 splice variant (VGLUT1v). Although we previously reported that VGLUT2 mRNA level of rat pineal gland at postnatal day 21 is higher in the nighttime than in daytime, questions remained as to the time of postnatal onset of this phenomenon and a 24-h change in the mRNA or protein level at postnatal days. The day-night difference in VGLUT2 mRNA level was evident 14 days after birth. In the adult, VGLUT2 mRNA and protein levels increased in the dark phase, with the protein level showing a 6-h delay. The nocturnal elevation in VGLUT2 mRNA level diminished under the constant light condition but persisted under the constant dark condition. The present data suggest that VGLUT2 in the rat pineal gland is involved in some nocturnal glutamatergic function.
松果腺在昼夜节律控制下通过夜间去甲肾上腺素能刺激分泌褪黑素，并表达囊泡谷氨酸转运体 (VGLUT) 1、VGLUT2 和 VGLUT1 剪接变异体 (VGLUT1v)。虽然我们之前报道过，21 日龄大鼠松果腺的 VGLUT2 mRNA 水平在夜间高于白天，但仍存在一些问题，即这种现象的出现时间以及在出生后几天内的 24 小时 mRNA 或蛋白质水平变化。出生后 14 天，VGLUT2 mRNA 水平的昼夜差异明显。在成年期，VGLUT2 mRNA 和蛋白水平在暗期增加，蛋白水平有 6 小时的延迟。在持续光照条件下，VGLUT2 mRNA 水平的夜间升高减弱，但在持续黑暗条件下仍然存在。本研究数据表明，大鼠松果腺中的 VGLUT2 参与了一些夜间谷氨酸能功能。
