Researchers found out how anesthesia works on plants

BERLIN, GERMANY - JULY 20: Venus fly traps sit on display at a presentation of carnivorous plants at the Berlin-Dahlem Botanical Garden on July 20, 2013 in Berlin, Germany. Carnivorous plants derive most of their nutrients by consuming animals, most commonly flying, foraging, or crawling insects, and have adapted to grow in places where the soil does not contain enough nutrients for them to survive. (Photo by Adam Berry/Getty Images)
Most of the surgical interventions today do not do without anesthesia. Whether it’s organ transplantation or simply tooth extraction, anesthesia is a necessary part of any operation.

Anesthesia was first used in 1846. For a long time for anesthesia doctors applied ether – a very effective, but equally unsafe means. Now, in the arsenal of an anesthetist, there are many compounds and drugs that reduce the sensitivity of the whole body (general anesthesia) and its separate part (local anesthesia).

The substances used differ in composition and properties, but they perform the same functions. However, the “mode of operation” and the peculiarities of the action of anesthetics remain not fully understood.

The international team of scientists decided to conduct an unusual experiment to find out what effect anesthesia has on plants. As noted in the press release of the American Council for Health and Science, the main purpose of this work is to find out whether plants can be used as model organisms for experiments.

It is known that plants react in principle to anesthetics. More than a hundred years ago, a French physician, the founder of endocrinology Claude Bernard, demonstrated that the mimosa shy ( Mimosa pudica ) reacts to diethyl ether. In ordinary life, this plant, as shown below, “folds” the leaves when touched (hence its name).

However, the anesthetic “turns off” this reaction: the leaves of the mimosa seem to lose their sensitivity. So Bernard and his colleagues came to the conclusion that anesthetics violate some natural processes, and this is true not only for animals, but also for plants.

In the new work, the authors used a wider sample of plants (all tests were carried out by an experimental group that was treated with an anesthetic and a control one).

Researchers started with the same mimosa shamefaced. The plant was treated with 15% diethyl ether. The leaves lost any reaction to sensory stimuli and did not respond to them even an hour after treatment.

Then the experts carried out a similar experiment with the Venus flytrap ( Dionaea muscipula ) – a predatory plant that is known for its slamming traps. On the surface of the leaves of the flycatcher are thin hairs that are highly sensitive and react to the slightest mechanical effect.

However, after treatment with ether, the flycatcher lost this property: multiple irritations of the hairs and leaves of the plant did not cause any reaction. However, the sensitivity was restored after 15 minutes after elimination of ether vapors.

Another carnivorous plant, Capsicum Capsicum ( Drosera capensis ), captures prey with sticky hairs on the surface of the leaves. They catch the insect, after which the edges of the leaf are closed. But under the influence of ether, the plant lost the ability to bend leaves and “tentacles”.

The same results showed experiments with peas inoculum ( Pisum sativum ), watercress ( Lepidium sativum ) and Arabian thistle ( Arabidopsis thaliana ).

But the most curious thing is that the “anesthetized” plants have lost not only sensitivity to touch. They have also changed some vital processes.

The results of the work published in the edition of Annals of Botany, suggest that the plants have slowed down action potentials – electrical impulses, which neurons use for communication. In fact, the action potentials are excitation waves moving along the membrane of a living cell. They arise when ions with different charges cross the neuron membrane.

In plants (as well as in humans and animals), the action potentials are slowed by anesthesia. And this means that plants can serve as a model organism for studying the actions of various anesthetics, the authors conclude.