

If you have seen The Rock, you might remember the scene in which

Nicholas Cage saves himself from nerve gas poisoning by jamming an atropine syringe into his chest. If his situation were real, the protagonist would have wanted a better antidote.

In the past two months, scientists in Korea and the Czech Republic may have discovered several of them. Both of the research teams reported their findings in Bioorganic and Medicinal Chemistry.

Nerve gas works by inactivating an enzyme that breaks down the nerve signal-sending chemical acetylcholine. That causes large amounts of the neurotransmitter to build up and overload the nervous system – resulting in a variety of terrible symptoms including convulsions and ending in respiratory failure.

Atropine is a drug derived from Atropa belladonna – the toxic berry better known as deadly nightshade. It blocks the signals sent by acetylcholine, providing relief from the chemical overload caused by nerve gas, but it is only a temporary fix.

At the Faculty of Military Health Sciences in Hradec Kralove, Czech

Republic, Kamil Kuca and his collaborators looked for chemicals that can counteract the particularly tricky nerve agent tabun. Although the chemicals they discovered could not accomplish that goal, they proved better than several established medications for mitigating the effects of paraoxon pesticide poisoning.

The other team tested several new chemicals on acetylcholine-destroying enzymes extracted from housefly brains and cow blood cells. Young-Sik Jung and his colleagues at the Korea Research Institute of Chemical Technology discovered a chemical that outperforms two of the standard treatments.

Both of the new medications, which belong to a family called oximes, reactivate the enzyme that destroys acetylcholine. In other words, they directly counteract the effects of nerve gas. Each one of them is a close relative of HI-6, 2-PAM, and TMB-4, which are currently used alongside atropine as the standard treatments for nerve gas poisoning.

Although nerve gas attacks are rare, they do happen. In 1995, the Aum

Shinrikyo cult released sarin into a Tokyo subway tunnel, killing several people and injuring hundreds. Far more common are cases of insecticide poisoning, which require the same medications. Insecticides are made from organophosphates, the same class of chemicals as nerve agents, but they are less harmful to humans in small doses.

Neither of the recent research projects included tests on humans or animals, so there is no way of knowing if the new chemicals are toxic.

If they do prove safe for humans, I wonder whether any of them will ever be adopted by the United States for homeland security programs.

In comparison to other countries, the American level of preparedness for a chemical attack seems rather low. Israel provides each of its citizens with an auto-injector that contains a blend of atropine and

TMB-4.

However, that level of preparation comes with its own set of problems.

A recent report described several incidents of kids accidentally stabbing themselves with the medicated darts. Thankfully, none of them suffered any serious consequences.

Photo Credit: Meridian Medical Technologies

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