第3巻 2007年10月　第4号

■基礎研究から学ぶ

1．神経科学シリーズ　GnRHニューロンに発現するイオンチャネル（1）
加藤　昌克
日本医科大学生理学講座（システム生理学）

1. Neuroscience Series Ion Channels in Rat Gonadotropin-Releasing Hormone Neurons (1)
Masakatsu Kato
Department of Physiology, Nippon Medical School

To understand neural mechanisms of reproductive physiology, we have generated promoter transgenic rats for gonadotropin-releasing hormone (GnRH) neurons. Using these rats we have analyzed ion channels expressed in rat GnRH neurons by means of patch clamp experiments and reverse transcriptase-polymerase chain reaction. The study revealed that rat GnRH neurons exhibit voltage-gated Na⁺, K⁺ and Ca²⁺ currents. There are delayed rectifier K⁺ currents, large conductance voltage- and Ca²⁺ -activated K⁺ currents (BK currents carried through BK channels) and Ca²⁺ -activated K⁺ currents (slow afterhyperpolarization currents carried through SK channels). Ca²⁺ currents are carried through five different Ca²⁺ channels, namely L-, N-, P/Q-, R- and T-types. Activation of these ion channels determines excitability of GnRH neurons and their firing pattern of action potentials.

日医大医会誌 2007; 3(4), 193-197

Key words
gonadotropin-releasing hormone neuron, Ca²⁺ channel, SK channel, BK channel, patch clamp

Correspondence to
Masakatsu Kato, Department of Physiology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan
E-mail：mkato@nms.ac.jp

受付：2007年6月28日　受理：2007年8月3日