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PubMed · 2900347

[Effect of beta-blockers on retinal function in vitro].

G Niemeyer·U Gerber·Y Uji
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Abstract

In an attempt to identify possible beta-adrenergic mechanisms in the cat retina the authors extended their previous studies on the effects of beta-agonists (Graefe's Arch. clin. exp. Ophthalmol. 225: 33-38, 1987) to three beta-adrenergic antagonists: propranolol, ICI 118.551, and timolol were applied in micromolar concentrations to the arterially perfused, dark-adapted cat eye. The rod ERG b-wave was generally depressed, sometimes enhanced after initial depression (propranolol), without showing any clear-cut dose-dependency. In contrast, the rod-mediated optic nerve action potential exhibited dose-dependent depression of the plateau and OFF components. All effects were reversible within 60-80 minutes. These results, in conjunction with earlier data on the effects of beta-agonists and recent biochemical and autoradiographic studies, strongly support the theory that there are beta-adrenergic synaptic mechanisms located in the inner layers of the mammalian retina.

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Adrenergic beta-AntagonistsAnimalsCatsDose-Response Relationship, DrugEvoked Potentials, VisualOptic NervePerfusionPropanolaminesPropranololRetinaTimololComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

G Niemeyer, U Gerber, Y Uji. 1988. [Effect of beta-blockers on retinal function in vitro].. https://doi.org/10.1055/s-2008-1050131

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