Plasma kisspeptin IR and serum reproductive hormone levels during iv infusion of kisspeptin-10 to healthy female volunteers in the follicular phase of the menstrual cycle. A–D, Time profiles for plasma kisspeptin IR (A) and changes in serum LH (B), FSH (C), and estrogen (D) during 4 h after commencement of a 90-min iv infusion of kisspeptin-10 to healthy female volunteers in the follicular phase of the menstrual cycle (n = 4–5 per group). For 720 vs. 20 pmol/kg · min: ***, P < 0.001. For 360 vs. 20 pmol/kg · min: ƒƒƒ, P < 0.001. For 180 vs. 20 pmol/kg · min: ψ, P < 0.05; ψψψ, P < 0.001. For 50 vs. 20 pmol/kg · min: Δ, P < 0.05. E–H, AUC for plasma kisspeptin IR (E) and changes in serum LH (F), FSH (G), and testosterone (H) during 4 h after commencement of a 90-min iv infusion of kisspeptin-10 to healthy female volunteers in the follicular phase of the menstrual cycle (n = 4–5 per group). **, P < 0.01; ***, P < 0.001. E2, Estradiol. Data are shown as mean ± sem.