Mechanisms for periodic and synchronized activity of GnRH neurons

点击翻译按钮获取中文摘要

Optical and multi-channel recording techniques were used to clarify the mechanisms for periodic and synchronized neuronal activity of GnRH neurons. Optical imaging with a voltage-sensitive dye revealed that activities of immortalized GnRH neurons (GT1-7cells) were synchronized. When a cell in contact with other cells was stimulated electrically, the evoked excitation was propagated to neighboring cells. The propagation of stimulus-evoked excitation was prevented by voltage-dependent Na^+ and Ca^<2+> channel blockers, but not by K^+ channel blockers. Multi-channel recording was made in cultured hypothalamic neurons that contains GnRH neurons. These neurons connected with each other were forming neuronal networks. Synchronized neuronal activity was found in neurons that made synapse-like contact. Immunohistochemical identification revealed that these synchronized neurons contained both GnRH and non-GnRH neurons. The present results suggest that activity of GnRH neurons is synchronized with not only other GnRH neurons but also non-GnRH neurons.