Browsing by Subject "Vacuoles"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    Open Access
    Autophagy in neurons a review
    (Murcia : F. Hernández, 2002) Larsen, K.E.; Sulzer, D.
    Macroautophagy is a process of regulated turnover of cellular constituents that occurs during development and under conditions of stress such as starvation. Defects in autophagy have serious consequences, as they have been linked to neurodegenerative disease, cancer, and cardiomyopathy. This process, which exists in all eukaryotic cells, is tightly controlled, but in extreme cases results in the death of the cell. While major insights into the molecular and biochemical pathways involved have come from genetic studies in yeast, little is known about autophagic pathways in mammalian cells, particularly in neurons. Recently, research in neuronal culture models has begun to identify some characteristics of neuronal macroautophagy. The results suggest that macroautophagy in neurons may provide a neuroprotective mechanism. Here, we review the defining characteristics of autophagy with special attention to its role in neurodegenerative disorders, and recent efforts to delineate the pathway of autophagic protein degradation in neurons.
  • Thumbnail Image
    Publication
    Open Access
    Pinocytotic vacuoles in human dental pulp capillaries
    (Murcia : F. Hernández, 1993) Lyroudia, K.I.; Economou, L.; Manthos, A.; Zervas, P.; Albanou, A.; Foroglou, Ch.
    Dental pulp capillaries were studied in human. They were of the cantinuous type, with the exception of a small number which were of the fenestrated type, located in the vicinity of the odontoblasts. A characteristic morphological peculiarity was found in the endothelial cells. In places there was a large quantity of multisized vacuoles. The vacuoles were evidently of pinocytotic origin, and their content was emptied into the extracapillary space. The initiation of their formation was indicated by the creation of cytoplasmic flaps, which could not be characterised as typical pseudopodia, and which in cross sections resembled microvilli. The flaps engulfed a quantity of plasma and then, after bending over, their edge fused with the cell, creating a vacuole. The vacuole, after being moved abluminally, was emptied into the pericapillary area by exocytosis. There was indication that flaps created at the borders of the endothelial cells (flanges) acted likewise, transporting vacuoles through the intercellular spaces. Micropinocytosis, was a distinctly different phenomenon, contributing, to a very small degree, to the intracellular enlargement of the vacuoles. It seems that this vacuolar mechanism of transportation serves an augmented metabolic need of the surrounding tissue.