Fritz Walter Lischka

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1. Effects of inositol-1,4,5-trisphosphate (InsP3) applied through a patch pipette to Xenopus laevis olfactory receptor cells (ORCs) were studied using the patch-clamp technique in conjunction with calcium imaging with fura-2. 2. InsP3 activated, first, a novel voltage-independent Ca2+ current (ICa) and, second, a nonselective cation current (Icat). 3. The(More)
We have studied olfactory receptor neurones under voltage-clamp conditions using the patch clamp technique. Application of sodium nitroprusside (SNP) activated a cation conductance if the GTP concentration in the pipette was in the millimolar range. With 10 microM GTP, SNP had no effect on the holding current but it abolished the normally occurring wash-out(More)
It is generally accepted that inositol-1,4,5-trisphosphate (InsP3) plays a role in olfactory transduction. However, the precise mode of action of InsP3 remains controversial. We have characterized the conductances activated by the addition of 10 microM InsP3 to excised patches of soma plasma membrane from rat olfactory neurons. InsP3 induced current(More)
Ca2+ ions enter neurones through various types of calcium and cation channels. The mechanisms by which Ca2+ ions are spatially buffered and expelled from neurones have been studied considerable less. Using calcium imaging in conjunction with the patch clamp technique, we investigated the Na/Ca exchanger in olfactory neurones and found evidence for its(More)
We asked whether specific mesenchymal/epithelial (M/E) induction generates olfactory receptor neurons (ORNs), vomeronasal neurons (VRNs), and gonadotropin-releasing hormone (GnRH) neurons, the major neuron classes associated with the olfactory epithelium (OE). To assess specificity of M/E-mediated neurogenesis, we compared the influence of frontonasal(More)
Olfactory receptor neurons employ a diversity of signaling mechanisms for transducing and encoding odorant information. The simultaneous activation of subsets of receptor neurons provides a complex pattern of activation in the olfactory bulb that allows for the rapid discrimination of odorant mixtures. While some transduction elements are conserved among(More)
Stimulation of olfactory receptor neurons (ORNs) with odors elicits an increase in the concentration of cAMP leading to opening of cyclic nucleotide-gated (CNG) channels and subsequent depolarization. Although opening of CNG channels is thought to be the main mechanism mediating signal transduction, modulation of other ion conductances by odorants has been(More)
Smokers regulate their smoking behavior on the basis of sensory stimuli independently of the pharmacological effects of nicotine (Rose J. E., et al. (1993) Pharmacol., Biochem. Behav.44 (4), 891-900). A better understanding of sensory mechanisms underlying smoking behavior may help to develop more effective smoking alternatives. Olfactory stimulation by(More)
Digital imaging and the patch clamp technique were used to investigate the intracellular calcium concentration in olfactory receptor neurons using the Ca2+ indicator dyes fura-2 and fura-2/AM. The spatial distribution of Cai2+ as well as its modification by the drugs Amiloride and Ruthenium Red were studied. Resting calcium concentrations in cells loaded(More)
The mucopolysaccharidoses (MPS) are a family of lysosomal storage diseases resulting in developmental defects and, in some types, mental retardation and other neurological symptoms. To gain insight into the neurological dysfunction in MPS, we examined the morphology of olfactory epithelia (OE) and physiology of olfactory receptor neurons (ORNs) in cat(More)