巴拉松對大白鼠運動神經元及運動終板超微結構的改變

巴拉松（Paraxon）為一有機磷化合物（organophosphatic compound），亦是一強而有力的殺蟲劑，同時也為一種不可逆的抗膽素脂酶（irreversible anti-cholinesterase），故當巴拉松與聯會（synapses）處的臟膽素脂酶（cholinesterase）結合以後會讓臟素脂酶失去活性，這也是巴松致毒的主因。我們使用大白鼠以巴拉松0.5mg/Kg/day皮下注射。從注射後30分鐘至21天，然後以電子鏡（electron microscopy）分別觀察大白鼠腰脊髓前角（anterior horn）及橫膈肌的運動終板（motor end plate）其漸進式的變化。在大白鼠腰脊髓前角，軸突的髓鞘（myelin sheath）隨著注射次數的增多及時間的增長，其鬆散的程度也更為加重，也就是去髓鞘（demyelination）的作用日益增加。並且在樹突，及軸突內可發現緻密板狀及膜狀的結構，道些結構也是退化的指標。另外對運動神經元（neurons）的胞體可以產生斑馬狀的Zebra body。巴拉松對於運動終板的影響，可以在聯會下組織出現顆粒性小泡（granular vesicles）。巴拉松對於聯會下組織造成傷害包括肌纖維的線粒體（mitochondria）產生空白斑痕（clear patch）及嵴（ridge）產生斷裂，而且使肌漿網（sarcoplasmic reticulum）及橫管（T tubule）產生明顯的擴張現象，以及產生膜狀螺環（membranous whorl）。

關鍵字

巴拉松；抗膽素脂酶；神經元；運動終板

並列摘要

Paraoxon is one of the organophosphatic compound that is a strong and powerful insecticide. In biochemistry, it is a irreversible antichlinesterase. When paraoxon interacts with cholinesterase at the synapses, cholinesterase will loss its biochemical activity. This is the major process of pathogenesis in paraoxon. Syraque-Dawley rats were given paraoxon by subcutaneous injection at a dosage of 0.5 mg/Kg/day. Thirty minutes to twenty-one days after injection of paraoxon the anterior horn of lumbar spinal cord and motor end plate of diaphragmatic muscle were observed under electron microscopy. At the anterior horn of lumbar spinal cord, axonal myeIin sheathes were puffy in appearance. The degree of puffy myelin worsend according to the times of injection and duration of time involved. We also discovered membranous and lamellar structures in the dendrites and axons. These structures are the indicators of degeneration. The cell bodies of neurons were able to create HZebra bodyH. At the motor end plate of diaphragmatic muscle, course granular vesicles to be found over subsynaptic organizations. Paraoxon also damages the subsynaptic organization including (1) clear patch and ridge disrupted at mitochondria (2) obviously dilated over sarcoplasmic reticulum and transverse tubules in muscle fibers (3) generated membranous whorl within the muscle fiber.

並列關鍵字

Paraoxon ； Anti-cholinesterase ； Neuron ； Motor end plate

國際替代計量

巴拉松對大白鼠運動神經元及運動終板超微結構的改變

全文下載

主題瀏覽