Influence of zinc on the normal and ischaemic retina

ISBN-13: 9783639168693 / Angielski / Miękka / 2009 / 188 str.

Marta Ugarte

Opis

In the mammalian retina, endogenous chelatable zincwas shown to be localised mainly in thephotoreceptors and retinal pigment epithelium. Zinclocalisation in the photoreceptors varied in lightand dark. Low (100 micromolar) levels of zincsulphate (ZnSO4) counteracted glutamate- andNMDA-induced lactate dehydrogenase release in ratcortical cultures; as well as the changes inGamma-aminobutyric acid (GABA)-immunoreactivitymediated by experimental ischaemia and NMDA inisolated rabbit retinas. However, high (500micromolar) levels of ZnSO4 caused lactatedehydrogenase release and alterations inGABA-immunoreactivity, and exacerbated the effects ofNMDA or ischaemia to the retina. When very low (1micromolar) concentrations of ZnSO4 were presentduring ischaemia, GABA-immunoreactivity was localisedto Müller cells, indicating that zinc prevents themetabolism of GABA in Müller cells in the ischaemicretina. High (500 micromolar) concentrations of ZnSO4potentiated reactive oxygen species formation whileameliorating lipid peroxidation. When low (1 nanomol)levels of ZnSO4 were injected into the vitreoushumour of the rabbit eye the retina remained unaffected.

O autorze

Marta Ugarte, DPhil MRCOphth: Studied Medicine at the University
of the Basque Country (Spain), did her DPhil at the University of
Oxford (UK) and trained in clinical ophthalmology in London and
Manchester. NIHR clinical lecturer in ophthalmology at the
University of Manchester (UK).