Ca2+ channels and Ca2+-activated K+ channels in adult rat gonadotrophin-releasing hormone neurones.

Gonadotrophin-releasing hormone (GnRH) neurones represent the final output neurones in the neuroendocrine system for the control of reproduction. To understand the reproductive neuroendocrine system, an investigation of the intrinsic and extrinsic properties of GnRH neurones is essential. In this review, we focus on the intrinsic properties and summarise our recent findings of ion channels expressed in rat GnRH neurones. Rat GnRH neurones express all four types of high voltage-activated Ca(2+) channel (L, N, P/Q, R) and the low voltage-activated Ca(2+) channel (T). GnRH neurones also express two types of Ca(2+)-activated K(+) [K(Ca)] channel: the small conductance Ca(2+)-activated K(+) (SK) channel and the large conductance Ca(2+)- and voltage-activated K(+) (BK) channel. The activities of these Ca(2+) and K(Ca) channels regulate cell excitability and cellular calcium homeostasis.