Development of calcium currents in cultures of mouse spinal cord and dorsal root ganglion neurones.
Cultured spinal cord (SC) and dorsal root ganglion (DRG) neurones of 11-13 day old foetal mice were investigated electro-physiologically during differentiation in vitro using the whole-cell patch-clamp technique. High-voltage-activated calcium currents (HVA) and low-voltage-activated (LVA) calcium currents were measured using barium ions as charge carrier. During differentiation in vitro the soma diameter of SC-neurones increased with age (0-42 days in vitro) from 10.3 +/- 2.7 microns to 25.1 +/- 5.9 microns. The capacitance of the soma increased from 7.4 +/- 2.3 pF to 34 +/- 6 pF. The inward calcium current amplitudes increased from 200 pA to 3 nA, while the LVA current amplitude increased only from 50 pA to 100-150 pA. The currents per membrane area through HVA calcium channels increased in the investigated time while the currents through LVA channels decreased.
Medical Institute of Environmental Hygiene, Heinrich-Heine-University, Department of Neurotoxicology, Düsseldorf, Germany.
U
U
Bickmeyer
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E
Müller
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H
Wiegand
D000818:Animals; D001464:Barium; D015220:Calcium Channels / Q000502:physiology*; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D005071:Evoked Potentials; D005727:Ganglia, Spinal / Q000502:physiology*; D005865:Gestational Age; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D009474:Neurons / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors
D015220:Calcium Channels; D001464:Barium; D013779:Tetrodotoxin