Oxytocin has long been considered the ‘love hormone’, but that belief may be starting to shake. A study published this Friday in the journal ‘Neuron’ suggests that this biological molecule is not essential for establishing a lasting bond with the couple and caring for the children.
The research was done with prairie voles, or voles, rodents renowned for their strong propensity for monogamy. After mating, these animals stay in pairs for life. They form very strong bonds and actively reject potential mates of the opposite sex. In addition, the male is as involved in the care of the offspring as the female. An example for our own species.
Previous studies using drugs to block oxytocin from binding to its receptor found that voles were unable to bind when hormone signaling was blocked. That is to say, his great qualities for love seemed to depend on this substance.
childbirth and parenting
Neuroscientists Devanand Manoli of the University of California San Francisco (UCSF) and Nirav Shah of Stanford raised the question. They used CRISPR gene-editing technology to generate fragments lacking functional oxytocin receptors. They then tested whether these mutant mice could form lasting bonds with their mates. To his surprise, he did it with the same ease as normal people.
A pair Vol. their ‘love’ is for life
The recipient was also eligible to pay for the birth and upbringing of the child. “The mutant voles can not only give birth, but also nurse,” says Shah. Both males and females engaged in normal parental behavior, licking and grooming, and were able to nurse the pups until they were young. However, women’s milk used to come out in limited quantities. As a result, younger pups lived to a shorter age, and those that were smaller.
The researchers believe that their results differ from those of other studies that used drugs to precisely block oxytocin receptor signaling. “Drugs can be messy, in the sense that they can bind to multiple receptors, and you don’t know which binding action is causing the effect,” Manoli says. Not so in the case of genetics.
autism and schizophrenia
Another important difference is that whereas most pharmacological studies suppress oxytocin receptor signaling in adult animals, this study turned it off when the voles were embryos. “We have found a mutation that begins before birth,” Shah explained. “It may be that there are compensatory or redundant pathways that are activated in these mutant animals and underlie the deficits in attachment, parental behavior and milk production,” he explains.
The illusion of oxytocin spray fades when it comes to redirecting a cheating wife or husband or even solving more serious problems. “People hoped that oxytocin would be a powerful treatment to help people with social cognitive deficits, such as autism or schizophrenia,” says Manoli. “But this research shows that there is probably no magic bullet for something as complex as social behavior,” he stresses.
