Abstracts - Deutsche Zoologische Gesellschaft

176 Neurobiology Posterslation of individual trigeminal nerve branches. Single current pulses (0.2ms, 1µA – 30mA) appliedvia suction electrodes were used for nerve stimulation. Field potentials in the LTTD consisted of apresynaptic P 0and a subsequent postsynaptic P 1component, with average latencies of 1.3 ± 0.2ms(P 0) and of 2.9 ± 0.4ms (P 1) at 14°C saline temperature. Similarly, in the optic tectum, field potentialsresulted from stimulation of the optic nerve. These results demonstrate that our in vitro-wholebrain-preparation remains functional for 2-3 days, thus, allowing stable long term-recordings fromIR-processing nuclei of the brain. This preparation will be further utilised for detailled studies on thecentral processing of IR-information.P NB.12 - ENPeptidomics of identified mammailian neurons by GAL 4 driven fluorescenceSusanne Neupert 1 , Andreas Husch 2 , Moritz Paehler 2 , Peter Kloppenburg 2 , Jens C. Brüning 3 , ReinhardPredel 11Institute of General Zoology and Animal Physiology, Friedrich-Schiller-Universität Jena;2Department of Biology, Institute of Zoology-Physiology, University of Cologne; 3 Institute of Genetics,University of CologneNeuropeptides are signalling molecules which shows remarkable chemical and functional diversityin invertebrates as well as in vertebrates, and are involved in neuromodulation, neurotransmission,and hormonal signalling. The identification of neuropeptides from specific tissues or even singlecells is an important step to understand physiological processes in an organism and to design novelexperiments. Here, we describe a protocol for the isolation of identified peptidergic cells from aspecific region of the mouse brain (pituitary gland) which contain POMC (proopiomelanocortin)expressing neurons. By using a Gal4 promoter line to drive green fluorescent protein (GFP) underUAS control, we first identified individual pituitary cells in tissue slices. These neurons were isolatedwith the help of a fluorescence stereo microscope direct from the fresh tissue and subjectedto MALDI-TOF mass spectrometry. The profilings of these fluorescence labelled cells resulted inreliable mass spectra, containing at least 12 products of the POMC prohormone. This method notonly allows the fast identification of neuropeptides on the single cell level but also the analysis ofcell-specific precursor processing.P NB.13 - ENEffects of cholinergic ligands on isolated identified leg motoneurons of stick insectsEugenio Eduardo Oliveira 1 , Joachim Schmidt 1 , Ansgar Büschges 1 , Vincent L. Salgado 2 , PeterKloppenburg 11Animal Physiology, University of Cologne; 2 BASF Corporation, Research Triangle Park, USAIn stick insect leg motoneurons (MNs) application of the muscarinic agonist pilocarpine elicits atonic depolarization (Büschges 1998) and a tonic depolarization in MNs during walking is blockedby the muscarinic antagonist atropine (Westmark 2007). From these studies it is not clear, if ACh hasa direct or an indirect effect on MNs, because these experiments were performed in the intact CNS.We started to characterize the effects of ACh and muscarinic agonists on dissociated MNs (in vitro).For identification MNs were backfilled with tetramethylrhodamine-dextran via the main leg nerve.Recordings from MN somata were performed in patch-clamp experiments in the whole-cell configuration.In almost all cells, application of ACh elicited inward currents, the amplitudes of whichvaried among cell. Currents consisted of a transient and a sustained component. Both componentswere ACh dose dependent, had very similar Hill’s parameters, were blocked dose dependently when