Blockage of voltage-gated calcium signaling impairs migration of glial cells in vivo

• Published in: Glia Vol. 50; no. 3; pp. 198 - 211
• Main Authors: Lohr, Christian, Heil, Jan E., Deitmer, Joachim W.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01-05-2005; Wiley-Liss
• Subjects: Animals; Biological and medical sciences; Brain - cytology; Brain - growth & development; Calcium Channel Blockers - pharmacology; Calcium Channels - drug effects; Calcium Channels - physiology; Calcium Signaling - drug effects; Calcium Signaling - physiology; Cell Movement - physiology; Chelating Agents - pharmacology; Denervation; development; Fundamental and applied biological sciences. Psychology; insect antennal lobe; Isolated neuron and nerve. Neuroglia; Manduca; Manduca sexta; Membrane Potentials - drug effects; Membrane Potentials - physiology; Neural Pathways - cytology; Neural Pathways - growth & development; Neuroglia - cytology; Neuroglia - physiology; Neuropil - cytology; Neuropil - physiology; olfactory glomeruli; Olfactory Pathways - cytology; Olfactory Pathways - growth & development; Olfactory system and olfaction. Gustatory system and gustation; Synapses - ultrastructure; two-photon calcium imaging; Up-Regulation - drug effects; Up-Regulation - physiology; Vertebrates: nervous system and sense organs; Glial cell; Calcium; olfactory glomeruli; Neuroglia; Insecta; Central nervous system; insect antennal lobe; Photon; two-photon calcium imaging; Encephalon; Cell motility; Signal transduction; Olfactory pathway; Arthropoda; Imaging; Development; Olfactory bulb; Olfactory glomerulus; Invertebrata
• ISSN: 0894-1491; 1098-1136
• DOI: 10.1002/glia.20163

Migration of glial cells is an essential step in the development of the antennal lobe, the primary olfactory center of insects, to establish well‐defined borders between olfactory glomeruli required for odor discrimination. In the present study, we used two‐photon microscopy to visualize calcium signaling in developing antennal lobe glial cells of the sphinx moth Manduca sexta. We found a correlation between the upregulation of functional voltage‐gated calcium channels and the onset of glial cell migration. In addition, glial cells migrating into the center of the antennal lobe express larger voltage‐gated calcium transients than glial cells that remain at the periphery. Migration behavior and calcium signaling of glial cells in vivo were manipulated either by deafferentation, by injection of the calcium channel blockers diltiazem, verapamil, and flunarizine, or by injection of the calcium chelators BAPTA‐AM and Fluo‐4‐AM. In deafferented antennal lobes, glial cells failed to express functional voltage‐gated calcium channels and did not migrate. Calcium channel blockage or reducing glial calcium signals by calcium chelators prevented glial cell migration and resulted in antennal lobes lacking glial borders around glomeruli, indicating that voltage‐gated calcium signaling is required for the migration of antennal lobe glial cells and the development of mature olfactory glomeruli. © 2005 Wiley‐Liss, Inc.