Figure 5: Schematic representation of the pattern of pulsatile and surge LH release.

Kiss1 neurons present intrinsic activity that leads to a basal level of tonic release of LH that is sufficient to maintain reproduction in males. In the presence of tachykinins, LH pulses acquire normal frequency and amplitude (red). In females, tachykinins are required for the formation of the preovulatory LH surge (red). Whether the action of SP/NKA and NKB is direct on Kiss1^AVPV/PeN neurons or through intermediate neurons, as well as the neuronal population that is the source of these tachykinins, remain to be deciphered.