Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 7 of 7

Full-Text Articles in Medicine and Health Sciences

Defects In Synapse Structure And Function Precede Motor Neuron Degeneration In Drosophila Models Of Fus-Related Als., Mohammad Shahidullah, Sylvain J Le Marchand, Hong Fei, Jiaming Zhang, Udai Bhan Pandey, Matthew B. Dalva, Piera Pasinelli, Irwin B. Levitan Dec 2013

Defects In Synapse Structure And Function Precede Motor Neuron Degeneration In Drosophila Models Of Fus-Related Als., Mohammad Shahidullah, Sylvain J Le Marchand, Hong Fei, Jiaming Zhang, Udai Bhan Pandey, Matthew B. Dalva, Piera Pasinelli, Irwin B. Levitan

Department of Neuroscience Faculty Papers

Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease that leads invariably to fatal paralysis associated with motor neuron degeneration and muscular atrophy. One gene associated with ALS encodes the DNA/RNA-binding protein Fused in Sarcoma (FUS). There now exist two Drosophila models of ALS. In one, human FUS with ALS-causing mutations is expressed in fly motor neurons; in the other, the gene cabeza (caz), the fly homolog of FUS, is ablated. These FUS-ALS flies exhibit larval locomotor defects indicative of neuromuscular dysfunction and early death. The locus and site of initiation of this neuromuscular dysfunction remain unclear. We show here …


Genetic And Anatomical Basis Of The Barrier Separating Wakefulness And Anesthetic-Induced Unresponsiveness., William J Joiner, Eliot B Friedman, Hsiao-Tung Hung, Kyunghee Koh, Mallory Sowcik, Amita Sehgal, Max B Kelz Sep 2013

Genetic And Anatomical Basis Of The Barrier Separating Wakefulness And Anesthetic-Induced Unresponsiveness., William J Joiner, Eliot B Friedman, Hsiao-Tung Hung, Kyunghee Koh, Mallory Sowcik, Amita Sehgal, Max B Kelz

Department of Neuroscience Faculty Papers

A robust, bistable switch regulates the fluctuations between wakefulness and natural sleep as well as those between wakefulness and anesthetic-induced unresponsiveness. We previously provided experimental evidence for the existence of a behavioral barrier to transitions between these states of arousal, which we call neural inertia. Here we show that neural inertia is controlled by processes that contribute to sleep homeostasis and requires four genes involved in electrical excitability: Sh, sss, na and unc79. Although loss of function mutations in these genes can increase or decrease sensitivity to anesthesia induction, surprisingly, they all collapse neural inertia. These effects are genetically selective: …


Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman Aug 2013

Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman

Department of Neuroscience Faculty Papers

Granule cells (GCs) of the dentate gyrus (DG) are considered to be quiescent--they rarely fire action potentials. In contrast, the other glutamatergic cell type in the DG, hilar mossy cells (MCs) often have a high level of spontaneous activity based on recordings in hippocampal slices. MCs project to GCs, so activity in MCs could play an important role in activating GCs. Therefore, we investigated whether MCs were active under basal conditions in vivo, using the immediate early gene c-fos as a tool. We hypothesized that MCs would exhibit c-fos expression even if rats were examined randomly, under normal housing conditions. …


Exploring Volatile General Anesthetic Binding To A Closed Membrane-Bound Bacterial Voltage-Gated Sodium Channel Via Computation., S G Raju, Annika F Barber, David N Lebard, Michael L Klein, Vincenzo Carnevale Jun 2013

Exploring Volatile General Anesthetic Binding To A Closed Membrane-Bound Bacterial Voltage-Gated Sodium Channel Via Computation., S G Raju, Annika F Barber, David N Lebard, Michael L Klein, Vincenzo Carnevale

Department of Neuroscience Faculty Papers

Despite the clinical ubiquity of anesthesia, the molecular basis of anesthetic action is poorly understood. Amongst the many molecular targets proposed to contribute to anesthetic effects, the voltage gated sodium channels (VGSCs) should also be considered relevant, as they have been shown to be sensitive to all general anesthetics tested thus far. However, binding sites for VGSCs have not been identified. Moreover, the mechanism of inhibition is still largely unknown. The recently reported atomic structures of several members of the bacterial VGSC family offer the opportunity to shed light on the mechanism of action of anesthetics on these important ion …


Serotonergic Innervation And Serotonin Receptor Expression Of Npy-Producing Neurons In The Rat Lateral And Basolateral Amygdaloid Nuclei., M Bonn, A Schmitt, K-P Lesch, E J Van Bockstaele, E Asan Mar 2013

Serotonergic Innervation And Serotonin Receptor Expression Of Npy-Producing Neurons In The Rat Lateral And Basolateral Amygdaloid Nuclei., M Bonn, A Schmitt, K-P Lesch, E J Van Bockstaele, E Asan

Department of Neuroscience Faculty Papers

Pharmacobehavioral studies in experimental animals, and imaging studies in humans, indicate that serotonergic transmission in the amygdala plays a key role in emotional processing, especially for anxiety-related stimuli. The lateral and basolateral amygdaloid nuclei receive a dense serotonergic innervation in all species studied to date. We investigated interrelations between serotonergic afferents and neuropeptide Y (NPY)-producing neurons, which are a subpopulation of inhibitory interneurons in the rat lateral and basolateral nuclei with particularly strong anxiolytic properties. Dual light microscopic immunolabeling showed numerous appositions of serotonergic afferents on NPY-immunoreactive somata. Using electron microscopy, direct membrane appositions and synaptic contacts between serotonin-containing axon …


Synchronous And Asynchronous Theta And Gamma Activity During Episodic Memory Formation., John F Burke, Kareem A Zaghloul, Joshua Jacobs, Ryan B Williams, Michael R Sperling, Ashwini D Sharan, Michael J Kahana Jan 2013

Synchronous And Asynchronous Theta And Gamma Activity During Episodic Memory Formation., John F Burke, Kareem A Zaghloul, Joshua Jacobs, Ryan B Williams, Michael R Sperling, Ashwini D Sharan, Michael J Kahana

Department of Neuroscience Faculty Papers

To test the hypothesis that neural oscillations synchronize to mediate memory encoding, we analyzed electrocorticographic recordings taken as 68 human neurosurgical patients studied and subsequently recalled lists of common words. To the extent that changes in spectral power reflect synchronous oscillations, we would expect those power changes to be accompanied by increases in phase synchrony between the region of interest and neighboring brain areas. Contrary to the hypothesized role of synchronous gamma oscillations in memory formation, we found that many key regions that showed power increases during successful memory encoding also exhibited decreases in global synchrony. Similarly, cortical theta activity …


Acute Activation, Desensitization And Smoldering Activation Of Human Acetylcholine Receptors., Barbara Campling, M.D., Frcpc, Alexander Kuryatov, Jon Lindstrom Jan 2013

Acute Activation, Desensitization And Smoldering Activation Of Human Acetylcholine Receptors., Barbara Campling, M.D., Frcpc, Alexander Kuryatov, Jon Lindstrom

Department of Neuroscience Faculty Papers

The behavioral effects of nicotine and other nicotinic agonists are mediated by AChRs in the brain. The relative contribution of acute activation versus chronic desensitization of AChRs is unknown. Sustained "smoldering activation" occurs over a range of agonist concentrations at which activated and desensitized AChRs are present in equilibrium. We used a fluorescent dye sensitive to changes in membrane potential to examine the effects of acute activation and chronic desensitization by nicotinic AChR agonists on cell lines expressing human α4β2, α3β4 and α7 AChRs. We examined the effects of acute and prolonged application of nicotine and the partial agonists varenicline, …