cocaine and honey bees

This article grabbed my attention because I am not used to seeing honey bees as an animal for the scientific testing of drugs.  Most of the drug studies done on animals I have heard about are done on rats or mice.  The reason this study was done on honey bees is because they are invertebrates.  Mammals, being vertebrates, become addicted to drugs mostly because of long-term adaptive responses to repeated use of the drug.  This article questions whether or not invertebrates have the same trend by injecting honey bees with cocaine and studying the way they respond.  The honey bees used were kept according to standard beekeeping practices and in standard commercial hives in order to keep the experiment consistent and with as few variables as could be.  Both cocaine salts (dissolved) and free base cocaine were used in these experiments on bees.  The study found that after repeated cocaine treatment, the honey bees developed a tolerance to the detrimental effects of large doses of cocaine.  Before this study, the only thing found in invertebrates during this kind of cocaine testing was a sensitisation.  When this study is added, the research shows that invertebrates have sensitisation and tolerance in response psychostimulant administration by using cocaine treatment.  The article posits that the tolerance and sensitisation that developed in invertebrates could be very similar to the way mammals develop these things.  The schedules and delivery regimes might have had something to do with this development, so future research could look at how one type of invertebrate species is affected by long-term cocaine treatment using different regimes.