Corticotropin-releasing Factor in Barrington's Nucleus

Barrington's nucleus is a collection of cells in the brainstem that projects to spinal cord neurons innervating the bladder. Based on lesion and stimulation studies, this nucleus has long been thought to be involved in the micturition reflex. Recently, Dr. Valentino noted that this nucleus contains one of the most dense clusters of corticotropin-releasing factor (CRF)-immunoreactive neurons in the brain. Since CRF is the primary brain hormone that initiates the stress response and that stress increases the synthesis of CRF in these neurons, she has proposed that Barrington's nucleus is involved in the regulation of autonomic function under stressful conditions. Dr. Valentino will systematically study this major CRF-containing brain nucleus and its possible role in stress. She will employ state-of-the-art anatomical methods to map the afferent and efferent connections of CRF-containing neurons of Barrington's nucleus in the brain. These studies will identify the neural circuitry by which stressors are able to communicate activity to this nucleus. In addition, Dr. Valentino along with her collaborator, Dr. Aston-Jones, will use electrophysiologic criteria to determine how different kinds of stressors alter activity of these CRF-containing neurons in this region. The results will not only provide new information about the function of Barrington's nucleus but may lead to a better understanding about how the brain integrates the multicomponent response to a stressor.