Aside from the intense and immediate pleasure of orgasm, there is also the warm, lingering post-orgasmic afterglow. This state, which is thought to be crucial for sexual pair bond formation, may be mediated, in both men and women, by release of the hormone oxytocin from the pituitary gland, under control of the hypothalamus. Treatments that block oxytocin release do not prevent orgasm or the immediate pleasurable sensations, but do seem to interfere with the crucial afterglow. It is worth noting that the oxytocin-releasing system appears to be involved in more general aspects of pair bond formation, not just that which occurs in a sexual context. Oxytocin surges occur in mothers’ brains at birth and during breastfeeding and are likely to be one important factor in developing a mother’s bond with her child.
Oxytocin nasal sprays, which effectively introduce oxytocin into the bloodstream, have been developed to help breastfeeding women who have a difficult time engaging the "milk let-down reflex" by which breastmilk is released during nursing. However, more recently, these sprays have been put to other uses. Experimental subjects who used oxytocin nasal spray before social encounters have been reported to be more trusting of strangers. Recently, Markus Heinrichs of the University of Zurich has reported that use of oxytocin nasal spray can reduce fear and thereby enhance interaction in persons with intense social phobias.
Not surprisingly, there are already people peddling oxytocin spray (or what they claim is oxytocin spray) on the internet. One brand is marketed as "Liquid Trust". Oy. Sounds better as a name for a rock-and-roll band.
The peptide hormone of the hour.