Avtor/Urednik     Potokar, Maja
Naslov     Mobilnost mešičkov v primarni kulturi astrocitov podgane in miši
Tip     monografija
Kraj izdaje     Ljubljana
Založnik     Univerza v Ljubljani, Medicinska fakulteta
Leto izdaje     2005
Obseg     str. 66
Jezik     slo
Abstrakt     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).
Deskriptorji     ASTROCYTES
EXOCYTOSIS
ATRIAL NATRIURETIC FACTOR
CALCIUM
CYTOSKELETON
TRANSFECTION
RECOMBINANT FUSION PROTEINS
MICROSCOPY, FLUORESCENCE
IMMUNOHISTOCHEMISTRY
MICROSCOPY, CONFOCAL
CELLS, CULTURED
RATS, WISTAR
MICE