Reproductive Signaling Study Kit

PT-141 is a cyclic heptapeptide melanocortin receptor agonist that activates MC3R and MC4R receptors in the central nervous system. Unlike PDE5 inhibitors which act on vascular smooth muscle, PT-141 acts directly on the hypothalamic melanocortin system to stimulate sexual neuroendocrine signaling and arousal through neural pathways. MC4R activation in the medial preoptic area and paraventricular nucleus triggers downstream signaling that enhances sexual motivation and arousal in both sexes.

Kisspeptin-10 is the minimal active fragment of the full-length kisspeptin encoded by the KISS1 gene. It binds to the KISS1R (GPR54) receptor on hypothalamic GnRH neurons, triggering a potent release of gonadotropin-releasing hormone (GnRH). This in turn stimulates pituitary gonadotrophs to release LH and FSH, making kisspeptin the most potent known stimulator of the reproductive endocrine axis. The kisspeptin/GPR54 system serves as the gatekeeper of puberty and fertility.

Oxytocin is a nonapeptide hormone produced in the hypothalamic paraventricular and supraoptic nuclei. It acts through the oxytocin receptor (OXTR), a G protein-coupled receptor, to stimulate uterine smooth muscle contraction during labor, milk ejection during breastfeeding, and social bonding behaviors. In the CNS, oxytocin modulates social cognition, trust, empathy, pair bonding, and anxiety reduction through actions in the amygdala, nucleus accumbens, and prefrontal cortex. It also has inflammatory-pathway and wound-repair biology properties.