Effects of kisspeptin on pulse intervals. A, Schematic of the predicted result if kisspeptin were to have no effect on the timing of endogenous pulses. Note that this is an idealized schematic and that actual pulse profiles show more variability in pulse intervals. B, The observed result, that kisspeptin delayed the appearance of the next endogenous pulse and prolongs intervals B and B2. C, Observed pulse intervals. Bars, means.