Working on ants as models, the most consumed anxiolytic, alprazolam, has been shown to have adverse effects. We presumed that plant extracts might be a safe alternative. A product made of an extract of Valeriana officinalis L., Humulus lupulus L., Passiflora incarnata L., and Ballota nigra L., easily available in any drugstore, was tested in the same way alprazolam had been. Contrary to alprazolam, this product did not significantly alter the ants" brood caring, cognition, behaviour in front of nestmates, tactile perception, learning and memory. It efficiently calmed the ants which often rested but not fully slept, avoided risky tasks and quietly reacted in a stressing situation. Adaptation occurred for the few adverse effects of this product (large sinuosity of movement, what had an effect on some behaviour).No habituation occurred as for its calming effect and it did not lead to dependence contrary to alprazolam. After its consumption ends, the calming effect of the plant extract slowly vanishes in 29 hours, step by step. In conclusion, this extract appears to be a safe product for reducing anxiousness and should be used preferentially to synthetized compounds which are known to have severe adverse effects.Keywords: aggressiveness, cognition, locomotion, memory, sleepiness.
IntroductionThe most consumed potions in the world are antidepressants, anxiolytics, antibiotics and hormones. Drugs of the two first categories may impact patients" behaviour, nervous system functioning and general activity. Usingants as biological models, we examined the effects of antidepressants (e.g.
Why using ants as biological models?Most biological processes are similar for all animals, including humans (i.e. genetics, metabolism, nervous cells functioning). Consequently, a lot of invertebrates and vertebrates are used as models for studying biological processes [3]. Invertebrates are more and more used due to their short life cycle, simple anatomy, and availability in large numbers [4]. Some species are largely used, for instance, the flatworm Dendrocelium lacteum, the nematode worm Caenorhabditis elegans, the mollusk Aplysia californica, the beetle Tribolium castaneum, the fruit fly Drosophila melanogaster, and the domestic bee Apis mellifera. Among invertebrates, insects, especially social hymenoptera and among them, bees, are advantageously used as models [5], but ants too can be used. Ants are among the most complex social invertebrates as for their morphology, physiology, social organization and behaviour. They are among the most morphologically evolved hymenoptera, having a unique resting position of their labium, mandibles and maxilla [6], as well as a lot of glands emitting numerous efficient pheromones [7]. Their societies are highly organized with a strong division of labor, an age-based polyethism and a social regulation [8]. Their behaviour is well developed: they care for their brood, build sophisticated nests, chemically mark the inside of their nest, their nest entrances, nest surroundings and foraging area ...