In humans, oxytocin is thought to be released during hugging, physical touch and orgasm in both sexes. In the brain oxytocin is involved in social recognition and bonding, and might be involved in the formation of trust between people and generosity.
Women are secreted in large amounts after distension of the cervix and vagina during labor and plays an important role in lactation by stimulating the nipples.
Effects of oxytocin in the brain
–Sexual arousal – Oxytocin injected into the cerebrospinal fluid causes spontaneous erections in rats.
–Autizam – Study in 1998 showed significantly lower levels of oxytocin in blood plasma of autistic children. Another study in 2003 showed a decrease in autism spectrum repetitive behaviors when oxytocin was administered intravenously. In 2007, a study reported that oxytocin helped autistic adults retain the ability for evaluating the emotional significance of speech intonation.
–Preparing Fetal neurons for delivery – through the placenta, maternal oxytocin reaches the fetal brain and leads to transferring the activity of the neurotransmitter GABA in inhibitory stimulating the fetal cortical neurons. This leads to “silence” in the brain of the fetus at the time of birth and reduces the vulnerability of hypoxic damage.
–MDMA (3,4-Methylenedioxymethamphetamine – ecstasy) – may increase feelings of love, compassion and connection to others by stimulating the activity of oxytocin by activating the serotonin 5-HT1A receptors, if initial studies in animals apply to humans.
Medicinal forms of oxytocin
Synthetic oxytocin can be found on the market as a drug under a different name or as generic oxytocin. Oxytocin is broken down in the gastrointestinal tract and must be administered by injection or nasal spray. Oxytocin has a half-life of typically about three minutes in the blood.
Intravenously does not reach the brain in significant amounts due to the blood-brain barrier. No evidence of entry of significant amounts of oxytocin in the CNS through a nasal spray. Topical preparations of oxytocin are used to stimulate breastfeeding but the efficacy of this approach is questionable.
Injected oxytocin analogues are used to induce labor and support labor in case of non-progressive delivery. Largely replaced ergotamine as the principal agent to increase uterine tone in acute postpartum haemorrhage. Oxytocin is also used in veterinary medicine to facilitate birth and increased secretion of milk.
“Hormone of love” may treat daily headaches?
The hormone oxytocin, which has been shown that it can increase confidence and social connectivity, according to a new study can be used as a treatment to relieve pain for those who suffer from frequent headaches.
Of the patients who had been given a dose of oxytocin as a nasal spray, 50% reported that their headaches are reduced by half, and a further 27% of these patients reported having no pain after four hours. By comparison, 11% of patients who were given placebo spray reported that their headache was reduced to half after four hours, but none of them pleaded for complete relief from pain.