Researchers from McGill University have identified a form of chemical signaling that mice use to protect their offspring. Researchers found that female mice approaching pregnancy and lactation increased stress hormones in male mice and even decreased their sensitivity to pain Sara Rosen et al. Summarized the paper "olfactory contact with late pregnant and lactating mice leads to stress analgesia in male mice", which was published in scientific progress.
"These findings are important for improving the reliability and repeatability of experiments involving mice." Jeffrey mogil, Professor of Psychology Department of McGill University and director of pain research E.P., commented: "this is another example that previously unknown factors in the laboratory environment can affect the results of scientific research."
According to co-author Sarah Rosen, "what may happen is that female mice are signaling to male mice that may be considering attacking their babies that they will vigorously defend them. It is the threat of possible imminent combat that leads to stress."
"Mice communicate more with each other than we think; just a lot of it is through smell," mogil said. Researchers began to look for responsible olfactory chemicals. Several odor sources have been identified, but one of them, n-amyl acetate, is released in the urine of pregnant and lactating female mice and is particularly effective in generating stress in male mice.
"Strangely, n-amyl acetate is also the reason for the unique smell of bananas." Co author Lucas Lima said: "after quickly going to the supermarket to buy some banana oil, we can confirm that the smell of banana extract has the same pressure on male mice as on pregnant female mice."
"This discovery represents a breakthrough in mammalian social signaling science." "There are many examples of male to female olfactory signals in rodents, but there are far fewer examples of female to male signals, especially outside the field of sexual behavior," mogil said
