| The lysosome is a motile, dynamic organelles. Which shows polymorphic structure, which are spherical in shape. Recently, the existence of acid phos-phatase - positive thread - like structure has been found in a number of cell types such as macrophages, endothelial cell, hepatocytes and pancreatic exo-crine cells, called " nematolysosorne" . These ACPse - positive thread - like structrers were connected with each other, forming a network - like system in the cytoplasm. The thread - like lysosomes may fuse to spherical lysosomes, and/or the lysosomes may be able to transform. It is possible that nematolysosomes mainly involve in the intracellular transport.In CNS, nematolysosome has been found in large pyramidal cell, Purmkin' s ceU and the motor neuron of spinal core. In the motor neurons of anterior horn of spinal cord, which distributes in cytoplasm and axon. It suggested that the nematolysosomes take part in the axonal transport.Vinculin is a kind of cytoskeletal proteins. Cytoskeleton includes microfila-ment, microtubule and intermediate filaments. F - actin is the main component of microfilament, which is formed by the polymerization of G - actin. In the inner surface of cell membrane, F - actin combines with other proteins such as vinculin, talin, a - actinin and fodrin to form membrane cytoskeleton and adher-ens - type junctions. So we call those proteins as actin binding proteins. Vinculin is a cytoskeletal protein associated with membrane actin - filament - attachment sites of cell - cell and cell - matrix adherens - type junctions, which responsible for the attachment of actin filaments to the plasma membrane. It demonstrates an important role in determining cell shape, adhesion, surface protrusive activity, cell locomotion and signal pathway.Lysosomes is a kind organelle derived from Golgi complex, which move actively through the cytoplasm to carry out their intracellular digestion, i. e. in heterophagy and autophagy. Macroautophagy can be described as a process involving four distinct events: (1) formation of primary lysosome; ( 2 ) formation of an early autophagosome and heterophagosome; (3 ) acidification of the phago-some, thereby becoming a late phagosome; ( 4 ) formation of autolysosome ( second lysosome) by fusion of the late phagosome with primary lysosome; and (5) hydrolysis of autolysosome contents resultion in its transformation into residual body. Nematolysosome are formed during the phagocytotic process, which regulated by cytosleletal system.It has been reported that F - actin facilitate the uptake of ligands and the fusing of late autophagosome and the primary lysosome, and actin binding proteins involve in these molecular mechanism in both steps. In the presence of cy-tochalasin D ( drug inducing the depolymerization of microfilaments) , the formation of the phagosome was inhibited in normal cultured rat kidney cells, and distribution of vinculin changes in corneal epithelial cells; PM A ( phorbol myristate acetate) - a actor of protein kinase C stimulates the appearance of nematolyso-somes and the redistribution of lysosome system in macrophages. On the other hand, PMA also induce formation of vinculin - associated focal contacts in carcinoma cell. These studies indicate that vinculin may be involved in the activities of phagosome/lysosome system. But if and how, it hasnt reported by now.We employed cell culture, histochemical, electron microscope and confocal laser scanning microscope methods, to study the distribution of vinculin and nematolysosomes in primary cultured neurons of spinal cord, and relationship between nematolysosomes and vinculin, so that we can further understand the function of cytoskeletal proteins in cellular activity and the formation and function of nematolysosomes.MethodsCell culture and Drug treatmentNeurons were derived from spinal cord of newborn rat. Briefly, spinal cord were cut into small pieces, and digested for 30 min at 37@ in the presence of 0.25% trypsin. Cells were mechanically dissociated in DMEM with 10%FBS, pla...
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