[Oxytocin, a mediator of anti-stress, well-being, social interaction, growth and healing].

The neuroendocrine and physiological systems related to pain and stress have long been subjected to study. More recently, the corresponding systems promoting anti-stress and restoration have also come into focus. It is not only important to investigate the mechanisms underlying disease but also to examine the physiological and psychological mechanisms which protect and heal the body and soul. The nonapeptide oxytocin, originally known to stimulate labour and milk ejection, appears to play an important role in this regard. Oxytocin can induce anti-stress-like effects such as reduction of blood pressure and cortisol levels. It increases pain thresholds, exerts an anxiolytic-like effect and stimulates various types of positive social interaction. In addition, it promotes growth and healing. Repeated exposure to oxytocin causes long-lasting effects by influencing the activity of other transmitter systems, a pattern which makes oxytocin potentially clinically relevant. Oxytocin can be released by various types of non-noxious sensory stimulation, for example by touch and warmth. Ingestion of food triggers oxytocin release by activation of vagal afferents. Most likely, oxytocin can also be released by stimulation of other senses such as olfaction, as well as by certain types of sound and light. In addition, purely psychological mechanisms may trigger the release of oxytocin. This means that positive interaction involving touch and psychological support may be health-promoting. The social interaction of daily life, as well as a positive environment, continuously activate this system. In addition, various types of psychotherapy involving transfer of support, warmth and empathy are likely to induce similar effects, which thus contribute to the positive effects of these kinds of therapies.