Oxytocin blocks alcohol intoxication symptoms

This joint 2015 Australian/German rodent study found that oxytocin bound to the brain receptors that cause loss of motor control with alcohol intoxication, and prevented rats from displaying these symptoms:

“While oxytocin might reduce your level of intoxication, it won’t actually change your blood alcohol level,” Dr Bowen said. “This is because the oxytocin is preventing the alcohol from accessing the sites in the brain that make you intoxicated, it is not causing the alcohol to leave your system any faster.”

Vasopressin didn’t have the same effect.

The level of alcohol used to produce this finding was roughly equivalent to a human drinking a bottle of wine over a few hours. Oxytocin didn’t prevent loss of motor control when the equivalent of a bottle of vodka was administered because the excess ethanol found its way into other brain receptors and put the rats to sleep.

The study showed oxytocin acting in its original functionalities such as water regulation rather than with its evolved social functions as described in How oxytocin and vasopressin were repurposed through evolution to serve social functions.

http://www.pnas.org/content/112/10/3104.full “Oxytocin prevents ethanol actions at δ subunit-containing GABA-A receptors and attenuates ethanol-induced motor impairment in rats”

Hypothalamic oxytocin and vasopressin have sex-specific effects on pair bonding, gregariousness, and aggression

This 2014 bird study showed the complementary effects of neurochemicals vasopressin and oxytocin in the hypothalamus.

Oxytocin neurons in the hypothalamus promote pair bonding and gregariousness in females.

Vasopressin neurons in the hypothalamus promote maternal care, social recognition, and gregariousness in both males and females, and aggression in males toward females.

Vasopressin and oxytocin released generally and in other parts of the brain have different effects. For example:

“Central administration of oxytocin also attenuates stress-induced effects on the brain and reverses stress-induced social avoidance.”

http://www.pnas.org/content/111/16/6069.full “Hypothalamic oxytocin and vasopressin neurons exert sex-specific effects on pair bonding, gregariousness, and aggression in finches”

How oxytocin and vasopressin were repurposed through evolution to serve social functions

This 2013 primate summary study showed how nonsocial behaviors, neurology and neurochemicals were repurposed through evolution to serve social functions.

Oxytocin and vasopressin retained their:

  • water regulation,
  • reproduction, and
  • anxiety relief

functionalities while they also evolved to become instrumental in:

  • pair-bonding,
  • parental care,
  • selective aggression,
  • social prominence,
  • generosity, and
  • trust.

http://www.pnas.org/content/110/Supplement_2/10387.full “Neuroethology of primate social behavior”