Sensory neurons that send signals from the intestines to the brain stem extend to the interface of areas of the intestine that are exposed to high levels of microbial compounds. Turning off the neurons, researchers observed activated neurons in the brainstem as well as activation of gut neurons that control intestinal motility. The findings shed light on the potential mechanisms behind neurological abnormalities and intestinal diseases, including IBS.
Researchers have identified a significant role dopamine plays in the development of heroin addiction. The study reports dopamine appears to directly cause drug reinforcement and, when dopamine neurons are silenced, mice are less likely to self administer the drug.