Physiology and pathology of the mammalian retina.

The retina is a part of the central nervous system and performs initial, but sophisticated computations for the analysis of visual signals. Apart from the workhorse neurotransmitters glutamate and GABA, several other molecules are employed as neuromodulators in the retina, notably, nitric oxide (NO), dopamine, serotonin and acetylcholine, among others. We are studying the role of neuromodulation in retinal signal processing and light/dark adaptation, using electrophysiological and live cell imaging techniques in combination with pharmacology and confocal/electron microscopical analysis.

The retina is exposed to several pathological threats. We are investigating the cellular and molecular mechanisms underlying the onset and progression of myopia in the developing retina, and the initial neuronal alterations underlying deteriorating vision in the earlier stages of diabetic retinopathy. Furthermore, we are evaluating the efficacy of photobiostimulation, the application of low-level long wavelength light to the retina, to stimulate mitochondrial activity and ameliorate the consequences of metabolic deficiencies associated with diabetic retinopathy. Both pathologies have growing incidences and are already affecting hundreds of millions of people worldwide. In this context, we are also trying to better understand general retinal metabolism, particularly glucose and lactate transport and consumption, which has remained an enigma for almost a century, in collaboration with F. Paquet-Durand in Tübingen, Germany.

1. Calbiague, V, Vielma, A.H., Cadiz, B., Paquet-Durand, F., Schmachtenberg, O. (2019) Physiological assessment of high glucose neurotoxicity in mouse and rat retinal explants. J. Comp. Neurol. 528(6):989-1002. doi: 10.1002/cne.24805.
2. Valdés, J., Trachsel-Moncho, L., Sahaboglu, A., Trifunović, D., Miranda, M., Ueffing, M., Paquet-Durand, F., Schmachtenberg, O. (2016) Organotypic retinal explant cultures as in vitro alternative for diabetic retinopathy studies. Altex, doi: 10.14573/altex.1603111.
3. Vielma, A.H. and Schmachtenberg, O. (2016) Electrophysiological fingerprints of OFF bipolar cells in rat retina. Sci. Rep., DOI: 10.1038/srep30259.
4. Couve, E., Osorio, R. and Schmachtenberg, O. (2013) The Amazing Odontoblast: Activity, Autophagy and Aging. J Dental Res. 92(9):765-72
5. Bazáes, A., Olivares, J. and Schmachtenberg, O. (2013) Properties, projections and tuning of teleost olfactory receptor neurons. (2013) J Chem Ecol. 39(4):451-64