Neuropharmacology

Biography

Biography: Robert Zorec

Abstract

Astrocytes are the most heterogeneous glial cell type in the brain. Initially, they were considered to be merely “nervenkitt” as proposed by Virchow in 1858, playing only subservient roles to neurons. However, in the last two decades, it is clear that these cells provide key homeostatic functions to brain. As in other eukaryotic cells, astrocytic vesicles have key cellular functions including constitutive housekeeping of the plasma membrane structure and cell-to-cell communication. Vesicle traffic is associated with cell surface morphology exhibiting distinct glial microdomains. These determine the signaling potential and metabolic huby for neighboring cells. Moreover, vesicles are used in astrocytes for the release of vesicle-laden chemical messengers. It is now clear that this process, regulated exocytosis, is orders of magnitude slower than that found in neurons. This lecture will address the properties of membrane-bound vesicles that store secretory gliosignal molecules, other recycling vesicles, and endocytotic vesicles that are involved in the traffic of plasma membrane receptors such as the class II major histocompatibility molecules and membrane transporters (aquaporin 4 and excitatory amino acid transporter 2). Vesicle dynamics depends on intermediate filaments therefore one has to consider that altered vesicle traffic may be associated with the diseases such as amyotrophic lateral sclerosis, multiple sclerosis, autistic disorders, Alzheimer’s disease, trauma, edema, and states in which astrocytes contribute to neuroinflammation. Indeed, in multiple sclerosis, for example, fingolimod, a recently introduced drug, apparently also affects vesicle traffic and gliotransmitter release from astrocytes, indicating that this process may well be used as a pharmacologic target for the development of new therapies.