0000000000314976
AUTHOR
Asunción Molowny Tudela
Searching free zinc at the ultrastructural level in cultured astrocytes
Zinc is an element that is necessary for many physiological functions in the body but may play an important role in diseases affecting most systems in the body if its balance is altered by environmental, toxicological or idiosyncrasy of subjects. We have centred our investigation in central nervous system, using cultured astrocytes since they are involved in clearance of zinc exocytated to the extracellular medium during synaptic transmission. In previous works we have used a zinc fluorochrome, i.e., the TSQ (6-Methoxy-(8-p-toluenesulfonamido)quinoline) to in vivo zinc uptake in cultured astrocytes and its accumulation in organelles named zincosomes. However, the precise location of these z…
Ethanol impairs extracellular zinc intake in cultured astrocytes
Zinc (Zn) deficiency is present in many physiological and health problems. Among circumstances involved in Zn deficiency, ethanol consumption appears as a prominent cause. In the CNS substantial amounts of Zn appear accumulated in synaptic vesicles of a particular class of neurons: the Zn enriched neurons very abundant in the telencephalon and cerebral cortex. This is the so called synaptic Zn which is simultaneously released with the neurotransmitter thus exerting a neuromodulator role during synaptic transmission. Neighbour astrocytic processes have to capture the excess of both extracellular Zn and neurotransmitter in order to maintain efficient synaptic transmission between neurons. In …
Extracellular zinc intake in cultured astrocytes is altered by ethanol exposure
Ethanol reduces the amount of intracellular zinc detectable with TSQ. Ethanol impairs astrocyte Zn management. It results in a lower capacity for exogenous Zn intake and delivering to zincosomes. Thus, Zn supplementation (dietary?) may not be enough for recovery of cellular normal function; as it happens in alcohol treated astrocytes. Zincosomes are a kind of low density primary endosomes.