Hydrogen Sulfide, Hydrogen Sulfide

It is produced from cysteine by various enzymes. It acts as a vasodilator and is also active in the brain, where it increases the response of the NMDA receptor and facilitates long term potentiation, which is involved in the formation of memory. Eventually the gas is converted to sulfites and further oxidized to thiosulfate and sulfate.Due to its effects similar to NO (without its potential to form peroxides by interacting with superoxide), hydrogen sulfide is now recognized as a potential cardioprotective agent.

The increased levels of hydrogen sulfide could have killed oxygen-generating plants as well as depleted the ozone layer causing further stress.

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