London, May 7 (Inditop.com) Traces of morphine in urine samples have been considered a clear proof of drug use in the past. But now a new study says that mice — and probably humans and other mammals as well — produce their own morphine in their bodies.

A study by a team of scientists from the Institute of Environmental Research at Technical University, Dortmund (TU-D), Germany, and the Donald Danforth Plant Science Centre, St Louis, Missouri, injected the mice with labelled tetrahydropapaveroline (THP) over a period of five days.

This chemical is the substance which the poppy plant converts into morphine in a complex process involving several steps. These steps, 17 altogether, were exactly what the scientists found in the mice.

“The animals have to possess an elaborate enzyme system which enables them to produce morphine autonomously,” explains Michael Spiteller, professor at the Dortmund Institute of Environmental Research.

Apart from one little difference in the early stages, the conversion process is the same in the animal and the poppy plant. According to Spiteller, evolution has obviously found two ways to synthesize morphine.

The purpose of the body’s own morphine production is still unclear. Morphine might help the nerve cells to communicate with one another, says a TU-D release.

But it is also possible that animals, and possibly humans too, use the production of morphine, for instance, under shock or in case of severe injuries as the body’s own painkiller.

The research was recently published in the Proceedings of the National Academy of Sciences.