Meeting Abstract

P2.125  Thursday, Jan. 5  Whole brain monoamine detection in a stalk-eyed fly BUBAK, A. N.*; SWALLOW, J. G.; RENNER, K. J.; Univ. of South Dakota

Male stalk-eyed flies (Teleopsis dalmanni) compete over territory and mates and provide an excellent model system to study aggression. In order to investigate the potential effects of serotonin (5-HT) on aggressive behavior in these flies, we developed a dissection and sample preparation method for whole brain that allows the detection of monoamines from a single fly using high performance liquid chromatography with electrochemical detection. The successful determination of the monoamines norepinephrine (NE), epinephrine (EPI), 5-hydroxytryptophan (5-HTP), dopamine (DA), 5-hydroxyindoleacetic acid (5-HIAA), tyramine (TA), and serotonin (5-HT) provide a means of assessing changes in stalk-eyed fly brain monoamine concentrations as a response to drug administration in the food media. This approach was successfully used to elevate 5-HT levels in stalk-eyed fly brains by oral administration of the precursor 5-HTP. We successfully increased 5-HT levels approximately 8 fold that of the mean control levels by orally administering 5-HTP and found that the response was dose-dependent. We are currently evaluating the time course over which serotonin remains elevated after the food source of 5-HTP is removed. The ability to manipulate neurotransmitter levels in the brain will allow us to develop experiments to explore the neurochemical mechanisms underlying behavioral interactions exhibited by stalk-eyed flies. Specifically, the method described to successfully raise 5-HT levels in the brain will be applied to intraspecific aggressive competitions as well as predator-prey interactions. The trials will be scored to determine if heightened levels of 5-HT have an impact on aggressive behavior and subsequent effects on dominance or survival. This work was supported by NSF grants IOS 0921874 and IOB 0448060.