Repeated Failure in Reward Pursuit Alters Innate Drosophila Larval Behaviors / 神经科学通报·英文版

Animals always seek rewards and the related neural basis has been well studied. However, what happens when animals fail to get a reward is largely unknown, although this is commonly seen in behaviors such as predation. Here, we set up a behavioral model of repeated failure in reward pursuit (RFRP) in Drosophila larvae. In this model, the larvae were repeatedly prevented from reaching attractants such as yeast and butyl acetate, before finally abandoning further attempts. After giving up, they usually showed a decreased locomotor speed and impaired performance in light avoidance and sugar preference, which were named as phenotypes of RFRP states. In larvae that had developed RFRP phenotypes, the octopamine concentration was greatly elevated, while tβh mutants devoid of octopamine were less likely to develop RFRP phenotypes, and octopamine feeding efficiently restored such defects. By down-regulating tβh in different groups of neurons and imaging neuronal activity, neurons that regulated the development of RFRP states and the behavioral exhibition of RFRP phenotypes were mapped to a small subgroup of non-glutamatergic and glutamatergic octopaminergic neurons in the central larval brain. Our results establish a model for investigating the effect of depriving an expected reward in Drosophila and provide a simplified framework for the associated neural basis.

Investigation of octopamine content in edible part of fishery products / 中国海洋药物

Objective To determine the content of octopamine,a kind of ?3-adrenergic receptor agonists in edible part of various fresh water and seawater aquatic products,and provide data for exploitation and utilization of octopamine in aquatic products.Methods After homogenate and ultrasound treatment,edible parts of fish,shellfish and cephalopodium were centrifugalized,then octopamine content in supernatant liquid was detected with HPLC.Results In eight kinds of fresh water fish,the octopamine contents of dorsal meat were generally higher than abdominal meat,which were in the range of 30~130?g?g-1 and roughly similar to seawater fish and freshwater shellfish.The octopamine contents in seawater shellfish were particularly high,almost dozens even thousands times of those in fish and freshwater shellfish.Cephalopodium also had a high content of octopamine while it was not detected in ocean algae.Conclusion Seawater mollusks are the most affluent resource of octopamine in aquatic products and ideal food of weight-watchers and diabetics.

Studies on separation of octopamine in fish sauce and affects on flavour of fish sauce / 中国海洋药物

Objective To establish a technical process for the separation of octopamine.MethodsTaking the absorptive capacity and elution efficiency of octopamine as indexes,the absorption characteristics and elution parameters of separation with macroporous resin were investigated.Results The static adsorption capacity of H103 type macroporous resin was 2.925mg g-1.The static elution ratio was 98.04%.Conclusion H103 type macroporous resin is effective to separate the octopamine and improve the flavour of fish sauce.

Analysis of adrenoceptor agonist-octopamine in fish sauce by HPLC / 中国海洋药物

Objective To establish a HPLC method for the determination of octopamine in fish sauce.Methods A phenomenes luna C18 column was used.The mobile phase was 0.02?g?mL-1 citric acid-0.02?g?mL-1 sodium dihydrogen phosphate(7∶3,v/v) and detection wavelength was 274 nm.Results The linear range of octopamine was 104.0%,RSD=1.53%.The detection limit was 5.7ng?mL-1.Conclusion This method is simple,rapid and reliable.It could be used for the determination of octopamine and its related substances in fish sauce.The content of octopamine in Engraulis japonicus sauce is 1055?g?mL-1.