Functional aspects of lysosomal organelles in blood platelets |
| |
Authors: | E Morgenstern E Walter E Weber |
| |
Institution: | (1) Institut für Zytologie und Elektronenmikroskopie der Universität des Saarlandes, Homburg (Saar);(2) Abteilung für klinische Pharmakologie der Medizinischen Universitätsklinik, Heidelberg |
| |
Abstract: | Summary Biochemical and ultrastructural findings from intact and fractionated pig and human blood platelets indicate the presence of different types of alpha granules. An electron dense type can be distinguished from a lighter one with a fibrillar matrix. The major part of the lysosomal hydrolases beta-glucuronidase and cathepsin is associated with the lighter granules. Most of the acid phosphatase appears in the vesicle fraction. The ultracytochemical investigation shows the acid phosphatase bound to both types of granules or vesicles. This enzyme is visible in the narrow spaces between the outer membranes of aggregated thrombocytes. Furthermore, there can be seen the transformation of alpha granules into vesicles and vesicles, which contain acid phosphatase releasing their contents into the extracellular medium. Thus the significance of the vesicle system for the release of substances out of the platelet seems to be proved. From this point of view the different types could be considered as alpha granules in different functional stages.Supported by Deutsche Forschungsgemeinschaft, Bonn-Bad Godesberg. |
| |
Keywords: | Blood platelets Lysosomes Acid phosphatase Aggregation Cell fractionation |
本文献已被 SpringerLink 等数据库收录! |