The Effect Of Several Attractants On Feeding Behavior And NPY Expression Of Barbodes Sinensis

Neropeptide Y(NPY), a 36-amino acid peptide, is abundantly and widely distributed in both the central nervous system(CNS) and the peripheral nervous System(PNS),especially in telencephalon, preoptic area, optic tectal slices and hypothalamus. NPY has been implicated in various physiological processes. It has, for instance, been established as important regulator of food intake and in the control of blood pressure in vertebrates. Moreover, NPY has been linked to the regulation of circadian rhythms and sexual behavior in mammals as well as in fish. Spinibarbus sinensis is a rare and economical fresh water breed in China, it is mainly distributed in the upper and medium reaches of Changjiang River and its branches. Spinibarbus sinensis is very delicious and nutritious, and it contains a large quantity of protein, fat, calcium, phosphorus and ferrum. NPY is an important regulator on food intake, but the molecular mechanisms of NPY in controlling Spinibarbus sinensis food intake have not been reported.In the research the special gene fragment of NPY from Spinibarbus sinensis was cloned, then feeding attraction activities of food attractants for Spinibarbus sinensis was investigated and analysed, at the same time, the real-time Q-PCR technology was applied and the express contents of Neuropeptide Y with the effect of food attractants was determined, primary results are as follows:1. Cloning the special gene fragment of NPY from Spinibarbus sinensisThe full-length cDNA sequence of NPY from Spinibarbus sinensis was obtained from the Genebank. Applying the Primer Express 5.0 software, a pair of special primers across one intron was designed for amplification of the special gene fragment of NPY from Spinibarbus sinensis.2.Brain tissue expression of NPYA semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay was developed to estimate tissue-specific expression of NPY gene in five different sections of the brain tissues of Spinibarbus sinensis. A pair of special primers across one intron was designed for amplification of the special gene fragment ofNPY from Spinibarbus sinensis. Amplification ofβ-actin cDNA was performed in order to confirm the steady-state level of expression of a housekeeping gene allowing an internal control for NPY gene expression.A strong preferential expression of NPY gene was observed in the telencephalon, deutencephalon, deutocerebrum, parencephalon and medulla oblongata.3.The effect of attractants on feeding behavior of Spinibarbus sinensisThe fishes cultured in the laboratory for two weeks before experiment. The method of glass labyrinth was applied, then feeding attraction activities of amino acids, nucleotide and crude extract from animal and plants were detected. With statistical analysis, the result of the feeding attraction activities of these food attractants is clam extract > nucleotide + betaine > 0.3% betaine > histidine + betaine > 0.2% betaine, 0.5% betaine > Gly + betaine > sea tangle extract, nucleotide + Gly, 0.1% betaine, 0.4% betaine > Gly +betaine +histidine, Gly > 0.6% betaine > nucleotide + histidine > nucleotide > Gly + histidine > histidine > nucleotide + Gly + histidine > garlic extract. The feeding attraction activities of betaine is not significant. The relation of the density and feeding attraction activities is not direct ratio.4.The effect of attractants on NPY expression of Spinibarbus sinensis On the basis of behavior experiments, several attractants were selected for furtherreal-time FQ-PCR experiment. NPY gene expression of Spinibarbus sinensis with the effect of clam extract, betaine and garlic extract was investigated. It was found that contents of NPY expression were correlated with attraction activity.