الفهرس 
Octopamine synthesis in invertebratesOnly 14 pages are availabe for public view
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Abstract
Effect of octapamine concentrations on negative geotaxis performance This experiment was conducted to explore the effect of octopamine concentrations(10-3 – 10-6 – 10-9 M ) on adult Drosophila performance in climbing assay. Interestingly ,the results indicate that there was no significant difference in the speed of negative geotaxis locomotion behavior of adult Drosophila male wild type Canton S neither after 3h nor 24h post-exposure when compared to control flies . VI.2.RNA interference: In Drosophila, four different types of receptors are present in octopaminergic neurons: OA2, OAMB, Octβ2R and Octβ3R receptors, But which receptor is the most important is still unknown. In this study, we focus on octopamine receptors to explore which one is responsible for walking coordination. This can be achieved by silencing these genes using GAL4/UAS technology with different driver lines and analyze walking behavior. VI.2.1. Universal RNAi interference of octopamine receptors The results of this study revealed that directing loss-of –function of octopamine receptors universally using tubP Gal4 leads to significant decrease in negative geotaxis performance of OAMB-deficient flies. VI.2.2. RNAi interference of octopamine recptors in nervous system While directing loss-of-function toward nervous system leads to significant decrease in negative geotaxis performance of all OA receptors. VI.2.3. RNAi interference of octopamine recptors in muscular system But only Oa2- and OAMB- muscular system deficient flies had significant decrease in negative geotaxis performance. VI.3. Effect of silencing octß2R, octß3R, OA2 and OAMB gene expression in adult Drosophila muscular tissue using mhc GAL4 driver on leg morphometric measurement To know whether octopamine receptor are important to keep leg muscles volume, silencing octopamine receptors in muscular system using mhc Gal4 followed by measuring leg parts length and width was done. Results revealed that silencing octß2R significantly decrease the width of fore- and hind leg coxa and the length of all fore leg parts but only significantly decrease coxa and trochanter of the hind leg. Silencing octß3R lead to significant decrease in the width of coxa, femur and tarsi of the fore legs and trochanter of the hind legs and the length of coxa, trochanter, femur and tarsi of fore- and hind legs. Silencing Oa2 significantly decrease the length of femur, tibia and tarsi of foreand hind legs. Silencing OAMB significantly decrease the width of hind leg coxa but significantly decrease the length of almost all parts. Silencing OAMB significantly decrease the width of hind leg coxa but significantly decrease the length of almost all parts. This explains a defect and Paralysis in insect movement In experiment of negative geotaxis for receptor OAMB. This study is a new study. We have been able to know the effect of octopamine on the parts of the legs of the dorsophila melanogaster and no one has ever studied this point. ENGLISH SUMMARY 74 VI.4.The effect of octopamine receptors silencing on ultrastructure leg muscles This experiment was conducted to explore the reason for impairment in the negative geotaxis performance octopamine receptors -deficient flies. These parameters are sarcomere length (Z-Z distance), myofibril and sarcoplasmic reticulum thickness and mitochondrial shape . The result indicated that there is significant decrease on thickness of myofibril of adult Drosophila in hind legs of octß2R , OAMB as compared as control. also,The result indicated that there is significant decrease on thickness of sarcoplasmic reticulum of adult Drosophila in hind legs of octß2R , OAMB ,Oa2 as compared as control . The result indicated that there is significant decrease on sarcomere thickness of adult Drosophila in hind legs of octß3R as compared as control . But,The result indicated that there is significant increase in size of mitocondria of adult Drosophila in hind legs of Oa2 as compared as control . VI.5.Histological changes of muscular tissue due to octopamine receptor silencing To know whether octopamine receptor are important to keep leg muscles architecture, silencing octopamine receptors in muscular system using mhc Gal4 followed by transmission electron microscopy was done. The results revealed that in OAMB - deficient flies, the leg muscles displayed abnormal morphologies of sarcomeres, disorganised myofibrils and mitochondrial abnormalities. The sarcomeres and the entire myofibrils showed loss of striations and structure. The sarcoplasmic reticulum around each myofibril was noticeably disintegrated; consequently, division of the muscle fibres into myofibrils was indistinct. Moreover, the myofibrils broke down forming spaces in the muscle fibre. The thickness of myofibrils that could be observed in the leg muscles of OAMBdeficient flies was significantly less than that the leg muscles of control flies. ZENGLISH SUMMARY 75 lines within the leg muscles of OAMB-deficient flies were split into smaller fragments that were dispersed among the sarcomeres. The mitochondria were electron lucent, enlarged with an irregular contour or small with a rounded contour and others were absent from certain areas of the muscle fibre. In addition, mitochondria were significantly larger in leg muscles from Octß1R and octBß 2R -defecient Drosophila than in control. The morphology of the Zline is altered upon octopamine receptors silencing. Octß1R deficient Drosophila showed complete disappearance of Z-lines in their leg muscles. Moreover, in Octß3R-defecient flies, the Z line was less well defined whereas inOctß2Rdefecient flies the Z lines were irregular and extended across entire sarcomere in a zigzag manner and consequently the myofibrils are narrowed, presumably the result of a loss of filaments and there is loss of fibril parallel organization. Electron micrographs of control Drosophila melanogaster leg fibrillar muscle show Z-bands with a highly ordered appearance. In conclusion, OctßRs are essential for insect muscular tissue architecture and for orchestration of the nervous system commands to motor neurons and muscular tissue responses. Knowledge gained from studies in Drosophila should help define the nature octopamine muscle– interactions, which are presumably related to the mechanisms functioning in mammalian muscles. Moreover, Octopamine receptors are considered very promising targets for the new groups of insecticides due to their absence from vertebrates.