MENLO PARK, CA--(Marketwire - July 16, 2008) - SRI International researchers have found that the direct interaction between two neuropeptide systems -- hypocretins/orexins (Hcrt) and nociceptin/orphanin FQ (N/OFQ) -- is responsible for stress-induced blockage of pain. Stress-induced analgesia (SIA) is a key component of the body's defensive behavioral "fight-or-flight" response. When individuals find themselves in life-threatening or other highly stressful situations, they are often able to ignore physical pain to accomplish tasks that might not otherwise seem possible. While the roles of certain neural substrates have been studied in the regulation of SIA, the neural pathways have been poorly understood until now. These new findings provide a better understanding of the critical role of these neuropeptides in SIA.
