| Author/Editor | Potokar, Maja | |
| Title | Mobilnost mešičkov v primarni kulturi astrocitov podgane in miši | |
| Type | monografija | |
| Place | Ljubljana | |
| Publisher | Univerza v Ljubljani, Medicinska fakulteta | |
| Publication year | 2005 | |
| Volume | str. 66 | |
| Language | slo | |
| Abstract | Research in recent years revealed that astrocytes, besides providing metabolic and structural support to neurons, play a more active role in the functioning of the central nervous system. These cells release many neuroactive substances, which are stored in membrane bound vesicles and may play a role in synapse modulation and in the coupling between neuronal activity and the local blood flow. These neuroactive substances are released into the extracellular space by regulated exocytosis. Before vesicles release ,their content into the extracellular space they need to be delivered to the site of the fusion with the plasma membrane. The mobility of vesicles containing neuroactive substances in astrocytes has not been studied yet. Here we used a green fluorescent protein tagged to preproatrial natriuretic peptide (proANP) to label single vesicles and dynamic microscopy to monitor their mobility. To accurately track labelled vesicles in time we employed a custom computer software to analyse movements of single vesicles in images recorded every 300 ms. Vesicle mobilities could be grouped into two groups, non-directional and directional. Non-directional vesicles remained close to the origin of tracking, while directional vesicles displayed an apparent directional mobility from the origin of tracking. Since the mean square displacement (MSD) in vesicles displaying non-directional movement is a linear function of observation time, it is likely that their movement is determined mainly by free diffusion. In contrast, the MSD relationship with time in vesicles displaying directional mobility, resembling a quadratic function, indicates that in addition to free diffusion other mechanisms of vesicle mobility may contribute to vesicle movements in astrocytes. Pharmacological studies confirmed the role of microtubules and relvealed the important role of actin filaments in the vesicle mobility in astrocytes. (Abstract truncated at 2000 characters). | |
| Descriptors | ASTROCYTES EXOCYTOSIS ATRIAL NATRIURETIC FACTOR CALCIUM CYTOSKELETON TRANSFECTION RECOMBINANT FUSION PROTEINS MICROSCOPY, FLUORESCENCE IMMUNOHISTOCHEMISTRY MICROSCOPY, CONFOCAL CELLS, CULTURED RATS, WISTAR MICE |