FIGURE 2.

Sexual satiety paradigms. During ad libitum copulation, sexually experienced male rats ejaculate repeatedly (≈ 7 E) before reaching sexual satiety. Twenty-four hours later, the majority of these males (≈ 70%) will not show sexual activity in the presence of a receptive female. Drug treatments administered prior to the copulation to satiety session that prevent the sexual inhibitory state indicate the involvement of the targeted system in their induction, while treatments administered 24 h after copulation to satiety that reverse the established sexual inhibition, indicate the involvement of the targeted system in the maintenance of the sexual inhibitory state (Rodríguez-Manzo and Fernández-Guasti, 1994). Sexual incentive motivation test: The apparatus consists of an elliptic open field arena with two diagonally opposed windows, which are separated from the arena with wire mesh, and communicate each with a removable cage where the incentive animals are placed. Incentive zones are designated in the arena, in front of each window. The incentive animals are introduced into the cages and the experimental male put into the center of the arena and allowed to freely ambulate. Sexual incentive motivation is measured as the time spent by the male rat in the incentive zones (receptive female or male) of the field. Sexually experienced males will spend more time in the incentive zone of the sexually receptive female than in the incentive zone of the male. Sexually satiated males will spend the same amount of time in both incentive zones. Figure modified from Canseco-Alba and Rodríguez-Manzo (2019a). Created with BioRender.com.