Science Editorial, October 5 (EFE).- A team of scientists has shown in mice that pregnancy hormones “rewire” the brains of female mice to prepare them for motherhood. Details of the research were published on Thursday in the journal Science.
The study, conducted by researchers at the Francis Crick Institute (UK), showed that two hormones, estrogen and progesterone, act on a small group of neurons in the brain to activate parental behavior before the arrival of offspring.
Furthermore, the researchers note that these adaptations generate stronger and more selective responses toward offspring.
For years it was thought that maternal behavior and maternal devotion to their offspring came from hormones released during birth, but later studies showed that mice born by Caesarean section and virgin mice exposed to pregnancy hormones also exhibited maternal behavior.
In the new study, the researchers found that female mice showed greater parental behavior late in pregnancy, before arriving and being exposed to pups.
The team discovered that the hormones estrogen and progesterone affect a group of neurons (galanin-expressing neurons) in an area of the brain called the middle preoptic area, in the hypothalamus, associated with rearing.
Thanks to brain recordings, they observed that estrogen simultaneously reduced the basal activity of these neurons and made them more excitable, while progesterone reshaped their inputs, recruiting more synapses (places of contact between neurons).
During the experiment, they made that group of neurons insensitive to hormones, completely eliminating the manifestation of parental behavior during pregnancy: the mice showed no commitment to the offspring even after birth, suggesting that there is a critical period of pregnancy in which these offspring are born. Hormones take effect.
Some of these changes persist for at least a month after birth, while others appear permanent, which also suggests that pregnancy can cause long-term changes in the female brain, according to the authors.
“We know that a woman’s body changes during pregnancy in preparation for raising her children. An example of this is milk production, which begins long before birth. Our research shows that these preparations also occur in the brain.” Leader of the state-based neuroprocessing laboratory at Crick.
“We believe that these changes, often called the ‘baby brain’, cause a shift in priorities: virgin mice focus on mating, so do not need to respond to the offspring of other females, while mothers need to perform strong parental behavior to ensure the survival of the offspring.”
“The amazing thing is that this change does not happen at birth: the brain prepares very early for this major biological change,” the researcher explains.
The researchers believe that the brain may also change in a similar way during pregnancy in humans, as the same hormonal changes are expected to affect the same areas of the brain.
The researchers point out that this could influence parental behavior along with environmental and social cues.
(c) EFE Agency
“Creator. Devoted pop culture specialist. Certified web fanatic. Unapologetic coffee lover.”