Keeping up the pressure
Dr. Assaf Ramot, a postdoctoral fellow in Prof. Alon Chen's group in the Institute's Department of Neurobiology, led the research pinpointing a small, previously unknown group of nerve cells in the paraventricular nucleus, or PVN, within the hypothalamus -- a part of the brain involved in regulating many of the body's reactions. These cells' position in the PVN led the researchers to suppose that the nerve cells play a role in the stress response. Prof. Chen explains that in the well-known stress response, the neurotransmitter corticotrophin releasing factor (CRF) is released from the PVN and goes to the pituitary gland. The pituitary gland releases hormones that then cause the adrenal gland to flood the bloodstream with the "stress hormone" cortisol. The cortisol, along with the regular stress response, lowers the production of CRF, thus causing a negative feedback loop in which the mechanism slows down and stops. A positive-feedback loop The newly di...