Clitoral stimulation induces conditioned place preference and Fos activation in the rat

Neurobiology of social attachments

“…When copulation occurs, the female rat is prepared not only to accept the male and receive sexual stimulation (clitoral and vaginocervical), but also her brain is in a hormonal state that facilitates learning. The effect of hormones, and sexual stimulation are required for female rats to develop conditioned partner preferences triggered by sexual stimuli (Parada et al, 2010;Corona et al, 2011;Parada et al, 2011;Pfaus et al, 2012).…”

The role of ovarian hormones in sexual reward states of the female rat

“…Depending on the condition, EB or oil was injected 48 h, and P or oil 4 h before each conditioning trial and/or CPP test. Hormone priming doses chosen for these experiments were based on previous studies done in our lab that consistently induce sexual receptivity in females (Parada et al, 2010(Parada et al, , 2011Pfaus et al, 1999).…”

“…CPP conditioning was conducted in 4 tri-colored PVC plastic rectangular chambers (21 × 21 × 68 cm) each containing three compartments separated by guillotine doors (as in Parada et al, 2010). The two large end compartments were separated by a smaller center choice compartment, which was used on the pre-exposure and final test days.…”

“…The time of the conditioning sessions, the number of trials, and the timing of the pre-test and final test was based on previous experiments conducted in our lab that reliably induced a significant CLS-CPP (Parada et al, 2010).…”

“…This copulatory CPP was abolished if females were given systemic injections of the opioid receptor antagonist naloxone prior to each conditioning trial , but not the mixed D1/D2 dopamine receptor antagonist flupenthixol (Garcia-Horsman and Paredes, 2004). Indeed, artificial clitoral stimulation (CLS) or vaginocervical stimulation (VCS) applied in a distributed manner over time to OVX rats primed with EB and P induced significant CPP (Meerts and Clark, 2009;Parada et al, 2010). Moreover, paced copulation or distributed CLS induce a conditioned partner preference in female rats for males bearing an odor (e.g., almond) associated with the sexual reward state (Coria-Avila et al, 2005;Parada et al, 2011), an effect that was abolished by systemic administration of the opioid antagonist naloxone for paced copulation (Coria-Avila et al, 2008a, 2008b but not flupenthixol (Coria-Avila et al, 2008a, 2008b, showing the dependence of sexual reward on the activation of opioid systems.…”