Rats dosed with Oxytocin because of the importance it plays with intimacy and bonding didn’t seem to get drunk on alcohol. Researchers at the University of Sidney injected large amounts of Oxytocin into rat’s brains which completely counteracted the inebriating effects of alcohol making them indistinguishable from a second group of rats who were totally sober. Oxytocin locks into GABA receptors in the brain essentially blocking the alcohol from getting there and causing intoxication.
Still, Oxytocin has its limits. After drinking the equivalent of a bottle of vodka the rats passed out. Presumably waking up the next day with wicked hangovers.