NEW YORK: The drug that helps zebras calm down after being chased by hungry lions may help human cope with far more mundane - but equally stressful - situations in everyday life. Californian scientists are working on a single injection that will help people relax without slowing down - in other words, the world's first vaccine for stress.
The quest to de-stress is being led by Dr Robert Sapolsky, professor of neuroscience at Stanford University, who after 30 years of research believes he can now alter the brain chemistry to create more "focused calm", a website said.
Dr Sapolsky said he was on the path to a genetically engineered alternative to yoga, pills and friends urging others to relax - itself a recognised cause of tension.
Chronic stress, as opposed to everyday worries, is linked to illnesses ranging from diabetes to heart attacks.
Dr Sapolsky, who first observed the damage caused by stress on animals in Kenya, has been working on hormones called glucocorticoids, which are part of the body's immune system and help to fight cancer and inflammation.
All mammals produce these hormones, which help them deal with a threat, often by running away.
Dr Sapolsky observed that, while a zebra will turn off the stress chemicals after escaping from a lion, modern man not only produces too many glucocorticoids in response to everyday alarms but cannot turn them off afterwards.
He says the hormone becomes toxic both biologically, by destroying brain cells and weakening the immune system and socially, when people continue to snap at friends hours after the original cause of tension vanished.
After early setbacks, the Stanford team adapted a herpes virus to carry engineered "neuro-protective" genes deep into the brain to neutralise the rogue hormones before they can damage the brain.
The virus is now shown to work on rats.
"To be honest, I'm still amazed that it works," Dr Sapolsky recently told Wired magazine.
He warns that human trials were years away, "but we have proved that it's possible".