Fig. 3.

Agonist-induced oscillatory calcium and current responses in identified gonadotrophs. A and B, Examples of Ca²⁺ responses to application of ACh and GnRH in gonadotrophs bathed in Ca²⁺-containing (A) and Ca²⁺-deficient (B) medium. C and D, Oxotremorine (OX) stimulated Ca²⁺ oscillations (C) and atropine inhibited effects of ACh on [Ca²⁺]_i response (D) in GnRH-responsive cells bathed in Ca²⁺-deficient medium. In this and following figures, arrows indicate the start of agonist application. E and F, Voltage clamp amphotericin-perforated whole-cell recording of Ca²⁺ oscillations monitored as an outward Ca²⁺-activated current in gonadotrophs stimulated with GnRH (E) and ACh (F). G, In a fraction of gonadotrophs, ACh stimulated inward and outward currents. All cells were voltage clamped at −60 mV. Horizontal bars indicate duration of agonist application.