Figure 3. Kisspeptin depolarizes GnRH neurons by affecting multiple ion channels.

Dotted-parallel lines indicate the switch from current to voltage clamp to establish IV curves (3-5 min duration) and omitted voltage sections are also indicated. A, Representative voltage trace showing kisspeptin depolarizing a GnRH neuron with an increase in Rin. The duration of depolarization is about 26 min. B, IV curves established by running a ramp from -20 to -120mV for 4s in voltage clamp. Solid line: an IV curve obtained before kisspeptin; dashed line: an IV curve during kisspeptin action; dotted line: an IV curve obtained by the point-by-point subtraction of currents during kisspeptin from those of control at corresponding potentials mathematically (the same for E and F). This shows that a kisspeptin-induced current reversed at -95mV. C, Representative voltage trace showing kisspeptin depolarizing a GnRH neuron with a decrease in Rin (responses to current injections (dots) are smaller during kisspeptin than control). D, IV curves and dotted line showing kisspeptin-induced current reversed at about -10 mV (estimated by extrapolating). E, Representative voltage trace showing kisspeptin depolarizing a GnRH neuron without any change in Rin (See IV curves in F). Note the kisspeptin application indication line is shorter than 3 min due to omitted trace during voltage recording. F, IV curves and dotted line showing kisspeptin-induced current did not reverse between -20 and -120 mV.