Some Physiological and Ethological Effects of Nicotine; Studies on the Ant Myrmica sabuleti as a Biological Model

Nicotine is one of the most consumed alkaloids. Its effects still lead to mixed conclusions. Having recently observed that ants could be used as biological models, we examined several physiological and ethological effects of nicotine using the ant Myrmica sabuleti as a biological model. We pointed out that nicotine increases the individuals’ locomotion, decreases the precision of their reaction, decreases their response to pheromones, does not impact their audacity, and reduces their food consumption. Nicotine largely decreases the individuals’ learning abilities when the reward does not contain this alkaloid but increases the rapidness of acquiring visual as well as olfactory conditioning when the reward contains nicotine. In the latter case, the final conditioning score is only very slightly higher than the control score, and there is no memorization. Under nicotine consumption, ants’ cognitive abilities seem of better quality, the ants in fact acting more rapidly. There is no habituation to nicotine consumption. No dependence on this alkaloid exists, as long as the individuals feel well, but dependence appears as soon as the individuals need something, are deprived of something. After nicotine consumption ends, a first slow, than a short rather quick, and finally again a slow decrease of its effects occurs. As for other alkaloids, no dependence is associated to no habituation and to rather slow vanishing of the effects. However, since the effects of nicotine quickly vanish during a short time, dependence might develop if the individual then encounters any problem or need. All the effects, here revealed using ants as biological models, are in agreement with those actually known for nicotine. Some effects could even be better defined, i.e. the impact on cognition, the occurrence of dependence. The present work brings so some new information about this important alkaloid and shows, once more, that ants could be used as biological models, for a first, not expensive step of a more general, biological or medical study.