Low and high exercise intensities differentially influence brain function, study shows
It is well-known that mice use olfactory receptors in the nose to sense odors, while specialized proteins work by sending the information about a particular scent to a selected brain region for processing. However, darcin and other pheromones are processed differently, as they communicate with another olfactory system, which is found in animals like mice but not in people.
Mice have two functional noses, with the first one working like that of humans, and the second one, dubbed as the vomernasal nose, is specialized solely for perceiving pheromones. Darcin changes brain activities
To arrive at their findings, the researchers studied the reactions of female mice on the pheromone darcin. They first exposed female mice to darcin-scented urine and assessed for their behavior. The team found that all of the female mice manifested immediate attraction to the chemical and after about 50 minutes, some females started leaving their own urinary scent markings.
When the team studied ultrasonic frequencies, they observed some of the female mice started to sing, which registered as a high-frequency sound that is too high for the human ear to hear. The behaviors manifested by female mice indicate sexual arousal. However, they also noted that not all the female mice reacted the same way, as lactating female mice, ignored the darcin-marked locations after the sniffing of the chemical.
The scientists believe that the reaction may depend on a brain region known as the medial amygdala, which contains a group of neurons, nNOS neurons, that activated when exposed to darcin. They also found the location of the neurons in the medial amygdala as interesting, since it serves a different role from the usual processing of emotional responses.
“Our results suggest that nNOS neurons in the medial amygdala do not simply pass along information about darcin. These neurons seem to be integrating sensory information about the pheromone with the internal state of the animal, such as whether she is a lactating mother and therefore not interested in mating,” Ebru Demir, PhD., an associate research scientist in the laboratory of Nobel Laureate Richard Axel, MD, at Columbia's Mortimer B. Zuckerman Mind Brain Behavior Institute, said. The study authors hope that the study findings provide an update on pheromones and their roles in the brain and behavior. Journal reference:
Demir, E., Li, K., Bobrowski-Khoury, N. et al. The pheromone darcin drives a circuit for innate and reinforced behaviours. Nature (2020). https://doi.org/10.1038/s41586-020-1967-8
Also in Industry News
How to decide whether or not to start treatment for prostate cancer?
Analysis of the SARS-CoV-2 proteome via visual tools
$65m investment increases British Patient Capital’s exposure to life sciences and health technology