Optical probing of neuronal circuits with calcium indicators.

An experimental difficulty in unraveling circuits in the mammalian nervous system is the identification of postsynaptic targets of a given neuron. Besides ultrastructural reconstructions, simultaneous recordings from pairs of cells in brain slices have been used to identify connected neurons. We describe in this paper a technique using calcium imaging that allows rapid identification of potential postsynaptic targets. This method consists of stimulating one neuron ("trigger") while imaging a population of cells to detect which other neurons ("followers") are activated by the trigger. By using bulk-loading of calcium indicators in slices of mouse visual cortex, we demonstrate that neurons that display somatic calcium transients time-locked to the spikes of a trigger neuron can be monosynaptically connected to it. This technique could be applied to reconstruct and assay circuits in the central nervous system.

[1]  A Grinvald,et al.  Identification of presynaptic neurons by laser photostimulation. , 1983, Science.

[2]  D. Whitteridge,et al.  Innervation of cat visual areas 17 and 18 by physiologically identified X‐ and Y‐ type thalamic afferents. II. Identification of postsynaptic targets by GABA immunocytochemistry and Golgi impregnation , 1985, The Journal of comparative neurology.

[3]  S. Brenner,et al.  The structure of the nervous system of the nematode Caenorhabditis elegans. , 1986, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[4]  F. Fay.  Optical methods in cell physiology. , 1986, Society of General Physiologists series.

[5]  Walter Heiligenberg,et al.  Neural Nets in Electric Fish , 1991 .

[6]  Rafael Yuste,et al.  Control of postsynaptic Ca2+ influx in developing neocortex by excitatory and inhibitory neurotransmitters , 1991, Neuron.

[7]  K. Stratford,et al.  Synaptic transmission between individual pyramidal neurons of the rat visual cortex in vitro , 1991, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[8]  T. Wiesel,et al.  Targets of horizontal connections in macaque primary visual cortex , 1991, The Journal of comparative neurology.

[9]  E. Callaway,et al.  Photostimulation using caged glutamate reveals functional circuitry in living brain slices. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[10]  E. White,et al.  Synapses of extrinsic and intrinsic origin made by callosal projection neurons in mouse visual cortex , 1993, The Journal of comparative neurology.

[11]  N. Tamamaki,et al.  Hippocampal pyramidal cells excite inhibitory neurons through a single release site , 1993, Nature.

[12]  D. Kleinfeld,et al.  Anatomical and functional imaging of neurons using 2-photon laser scanning microscopy , 1994, Journal of Neuroscience Methods.

[13]  Peter Somogyi,et al.  Diverse sources of hippocampal unitary inhibitory postsynaptic potentials and the number of synaptic release sites , 1994, Nature.

[14]  J Deuchars,et al.  Relationships between morphology and physiology of pyramid‐pyramid single axon connections in rat neocortex in vitro. , 1994, The Journal of physiology.

[15]  Rafael Yuste,et al.  Ca2+ accumulations in dendrites of neocortical pyramidal neurons: An apical band and evidence for two functional compartments , 1994, Neuron.

[16]  E. Marder,et al.  Principles of rhythmic motor pattern generation. , 1996, Physiological reviews.

[17]  D. Johnston,et al.  Active properties of neuronal dendrites. , 1996, Annual review of neuroscience.

[18]  H. Markram,et al.  Redistribution of synaptic efficacy between neocortical pyramidal neurons , 1996, Nature.

[19]  B. Sakmann,et al.  Ca2+ buffering and action potential-evoked Ca2+ signaling in dendrites of pyramidal neurons. , 1996, Biophysical journal.

[20]  R. Tsien,et al.  Fluorescent indicators for Ca2+based on green fluorescent proteins and calmodulin , 1997, Nature.

[21]  A. Persechini,et al.  Detection in Living Cells of Ca2+-dependent Changes in the Fluorescence Emission of an Indicator Composed of Two Green Fluorescent Protein Variants Linked by a Calmodulin-binding Sequence , 1997, The Journal of Biological Chemistry.

[22]  Ehud Y Isacoff,et al.  A Genetically Encoded Optical Probe of Membrane Voltage , 1997, Neuron.

[23]  D. Kleinfeld,et al.  Functional study of the rat cortical microcircuitry with voltage-sensitive dye imaging of neocortical slices. , 1997, Cerebral cortex.

[24]  Rafael Yuste,et al.  Imaging neurons : a laboratory manual , 1999 .

[25]  R. Schwartz-Bloom,et al.  Fluorescence imaging of changes in intracellular chloride in living brain slices. , 1999, Methods.

[26]  Timothy W. Cacciatore,et al.  Identification of Neural Circuits by Imaging Coherent Electrical Activity with FRET-Based Dyes , 1999, Neuron.

[27]  R. Yuste,et al.  Detecting action potentials in neuronal populations with calcium imaging. , 1999, Methods.

[28]  D. Wilkin,et al.  Neuron , 2001, Brain Research.