X-Message-Number: 11641 From: "Stephen Bogner, P.Eng." <> Subject: Nitric Oxide confirmed as a regulator for Cell Death Date: Thu, 29 Apr 1999 13:25:38 -0600 Researchers at the Howard Hughes Medical Institute (HHMI) at Duke University in collaboration with scientists at the Dana-Farber Cancer Institute have now found that nitric oxide (NO), a well-studied molecule implicated in a host of communication pathways in and between cells, is also a switch that controls whether cells live or die. ... Stamler and his colleagues found that NO molecules occupy a critical site on the enzyme caspase, a molecular "executioner" within human cells. When occupying this site, NO effectively plugs a communication pathway that activates caspase and triggers cell death. "We showed that nitric oxide sits on the site and keeps the enzyme inactive," said Stamler. "Conversely, the nitric oxide is removed in cells programmed to die. Simply put, if you block nitric oxide production within the cell, you make the cell more susceptible to cell death. And if you add it back, you prevent cell death." Apoptosis can be triggered through a biochemical chain of events known as the Fas pathway. When activated, the Fas pathway initiates a cascade of signals within the cell that ultimately turns on caspase. When NO occupies the site on caspase, however, the death message is blocked. Fas somehow manages to pop the nitric oxide off the cells that are programmed to die. ... "We'd like to think modulation of the nitric oxide system can be used for therapeutic gain," he said. The complete article can be found at: http://www.hhmi.org/news/stamler.htm The reason that I think that this might be of interest to cryonet is because it may have implications for the medication protocol that might be used to limit damage prior to or during suspension. This is not my area of expertise - so someone knowledgeable may want to comment. Regards (and long life); Steve. Stephen Bogner, P.Eng. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=11641