Oxytocin is suppose to counteract the stress hormone cortisol. I believe I read that at this lady's website.
http://www.self-compassion.org/
I remember her saying that you can release oxytocin in yourself by giving yourself a hug or simply putting a hand over your heart.
Oxytocin is more abundant in females rather than males mammals. Breast feeding releases a lot but also having sex with a partner releases a lot.
There seems to be and inverse relationship between testosterone and oxytocin. Recently I watched a documentary on this male soccer team forming. As the team members were bonding oxytocin would be released. As a team member became self absorb in individual play testosterone would be released. The narrator stated that testosterone could be described as being the selfish hormone while oxytocin could be described as the selfless hormone. Maybe that is how it fits in with being helpful concerning schizophrenia. I have observed that in schizophrenia there seems to be a major focus on the self such as self consciousness, self esteem, and paranoia or an over concern for one's self. Just my theory.
One more piece of trivia, we men become fathers they are shown to then have lower levels of testosterone which probably means there is more oxytocin floating around in their blood stream.