Analysis And Determination Of Monoamine Neurotransmitters And Metabolic Enzymes In The Brain Of Honey Bees (Apis) In Different Behavior States

As one of the most typical social insects,honeybees perform complex social behavior.It’s the assurance that all kinds of worker bees to perform their roles to maintain the colony construction.This study focused on how monoamine neurotransmitters and their metabolic enzymes,an important neural modulator in invertebrates’ central nervous system,regulate honeybees behaviors,such as nursing,foraging and dancing.First,we developed a high liquid chromatography-electrochemical method to detect seven monoamine neurotransmitters simultaneously in honeybee brains.Monoamine transmitters and their metabolites were isolated by an Acclaim C18 column(2.2 μ m,2.1 × 100 mm)in 38℃ with mobile phase,which consists of NaH2PO4,sodium 1-octanesulfonate,citric acid,EDTA and acetonitrile,at 0.2mL/min in flow rate.After proteins of honeybee brains were precipitated by mixture of perchloric acid,Na2OsS2 and EDTA,10μL supernatant was filtrated with 0.22μm membrane as loading solution was detected at 300mV.This method could be applied in quantity determination of monoamine neurotransmitters and their metabolites in honeybee brains by reason of its high detection sensitivity,fine precision and operability.Second,using the methods we set to measure the concentration of monoamine neurotransmitters and their metabolites in honeybees’(Apis mellifera and Apis cerana)brains.The content of norepinephrine in both Apis mellifera and Apis cerana foragers’ brains were significantly higher than nurses,whereas other substances content showed little differences.The content of norepinephrine in Apis mellifera just-started dancers’ brains was significantly lower than foragers,just-ended dancers and once-danced-but-now-quiet dancers.On the contrary,the content of dopamine in Apis mellifera just-started dancers’ brains was significantly higher than just-ended dancers,indicating these two neural substances are involved in regulating bee dance behavior.In addition to nurse worker bees,the content of all neural analysts and their variation pattern in other worker bees’ brains were different between Apis mellifera and Apis cerana.Third,we tested the activity of monoamine neurotransmitters metabolic enzymes in honeybees’(Apis mellifera and Apis cerana)brains.The results showed that catecholamine neurotransmitters were involved more widely in bee nursing,foraging and dancing behavior than indoleamine neurotransmitters.The specific activity of dopamine beta hydroxylase,which is the synthetase of norepinephrine,in just-started dancing bees’ brains were significantly higher than just-ended dancing bees.We inferred that norepinephrine was related to the honeybee dance behavior.There was no difference not only the content of monoamine neurotransmitters but also the specific activity of their metabolic enzymes between Apis mellifera and Apis cerana nurse worker bees’ brains,therefore we concluded these two species had similar neural regulation mechanism on nursing behavior.