In my laboratory, we investigate different aspects within the field of sensory physiology:
- Modulation of sensory processing in the mammalian retina (refs. 6,9,11).Apart from the workhorse molecules glutamate, GABA and glycine, several other neurotransmitters modulate retinal signal processing, e.g. dopamine, serotonin, acetylcholine and others. We focus on the cellular and molecular actions of a peculiar neuromodulator, nitric oxide (NO), a short-lived and highly diffusible molecule that acts through activation of soluble guanylate cyclase or S-nitrosation of proteins. Using single and paired patch clamp in combination with DAF-2 live cell imaging followed by confocal microscopy, we identify the sources and targets of NO in the retina and analyze its molecular mechanism of action (ref. 6). Currently, we are deciphering the modulation of the retinal OFF-pathway by NO (manuscript in preparation).
Furthermore, we are studying the role of Pannexin-1 channels in retinal ganglion cells. Pannexins are structurally similar to connexins, but share no sequence homology with them. If they form intercellular channels under certain conditions remains a matter of dispute. We use patch clamping, pharmacology, immunohistochemistry and Panx-1 ko mice as controls to understand the role of these channels in retinal ganglion cells.
- Olfactory transduction and coding in teleost fishes (refs. 1,3,5).The marine environment imposes specific characteristics on the sensory organs of its inhabitants. We study olfactory transduction and coding in teleosts, applying electrophysiology, calcium imaging and histological techniques. During recent years, we have been investigating a peculiar type of olfactory receptor neuron, called crypt cell, which might represent a specialized detector for con-specific odorants or pheromones (ref. 5). Fish are also great models to study olfactory coding in the olfactory bulb and higher brain centers. We perform simultaneous recordings from the olfactory organ (EOG), the olfactory bulb or the telecephalon in anesthetized live rainbow trout to understand the coding principles for different classes (food-related, social and sexual) of odorants.
- Nerve sprouting and neuronal plasticity under caries infection in human teeth (refs. 2,4,7).
In a collaboration with Eduardo Couve and his laboratory, we use immunohistochemistry, confocal and electron microscopy on healthy and caries-infected teeth to understand the dynamic neuro-immune response of the dental pulp to progressive disease stages.
- Osorio, R. and Schmachtenberg, O. (2013) Calcium-activated chloride channels do not contribute to the odorant transduction current in the marine teleost Isacia conceptionis. J Fish Biol. 83(5): 1468-1473
- Couve, E., Osorio, R. and Schmachtenberg, O. The Amazing Odontoblast: Activity, Autophagy and Aging. J Dental Res. 92(9):765-72
- 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. Cover.
- Couve, E., Osorio, O. and Schmachtenberg, O. (2012) Mitochondrial Autophagy and Lipofuscin Accumulation in Aging Odontoblasts. J Dental Res 91(7): 696-701. Cover.
- Bazáes, A. and Schmachtenberg, O. (2012) Odorant Tuning of Olfactory Crypt Cells from Juvenile and Adult Rainbow Trout. J Exp Biol 215:1740-1748.