"Understanding how mice process cues from the olfactory system--which regulates the sense of smell--should provide insight into the fundamental principles that mammalian brains use to transform sensory information into behavior," says lead investigator Nirao Shah, MD, PhD, UCSF assistant professor of anatomy.
"There are striking genetic and neuroanatomic similarities between mice and humans. We hope that such basic knowledge of how the brain functions will eventually be useful in understanding how the human brain generates behaviors in humans," he adds.
The UCSF study focused on the sexual and aggressive behaviors triggered by the rodent's olfactory system. The findings are published in the December issue of Nature Neuroscience.
According to Shah, researchers traditionally have thought rodents detect pheromones through a specialized organ--the vomeronasal organ (VNO) in the nose--that is separate from the main olfactory system. Pheromones are olfactory cues that signal the social and sexual status of individuals of a species, and their detection is a key step in regulating behaviors such as mating and aggression.
The new study findings show, however, that male mice require intact functioning of the main olfactory epithelium (MOE) in order to detect pheromones that elicit sexual behavior and fighting. The MOE covers the olfactory region of the nasal cavity and contains sensory neurons that recognize odors and transmit this information to the brain.
The study is important, says Shah, because it establishes a novel and hitherto unsuspected role for the MOE in regulating mating and aggressive behavior in mice. He adds that while it appears humans do not have an intact VNO, they do possess a functioning MOE.
In the study, researchers compared the behavior of mutant male mice
Source:University of California - San Francisco