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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, RESULTS. Meshes: Animals, Brain, Cocaine, Dopamine Uptake Inhibitors, Dose-Response Relationship, Drug, Drosophila melanogaster, Male, Mixed Function Oxygenases, Mutation, Octopamine, Time Factors, Tyramine, Tyrosine, Tyrosine Decarboxylase.
user
Is the trace amine tyramine essential for sensitization to cocaine in Drosophila? Context: Sensitization to psychostimulant drugs of abuse is thought to be an important aspect of human addiction, yet how it develops is still unclear. The development of sensitization to cocaine in the fruit fly Drosophila melanogaster is strikingly similar to that observed in vertebrates. By taking advantage of the powerful genetic approaches that are possible in Drosophila, we are able to identify and characterize mutants that fail to develop sensitization. We found that the Drosophila mutant inactive (iav) failed to become sensitized to cocaine. Mutant flies had reduced amounts of the trace amine tyramine in the brain because of reduced activity of the enzyme tyrosine decarboxylase (TDC), which converts tyrosine to tyramine. Furthermore, cocaine exposure induced TDC enzyme activity in a time-dependent manner that paralleled the development of behavioral sensitization. The sensitization failure of iav flies could be rescued by feeding the flies with tyramine; other biogenic amines or amine precursors did not have the same effect.
assistant
These results indicate an essential role for tyramine in cocaine sensitization in Drosophila. Final Decision: yes