Module 10: Figure Ca2+ signals in spines and dendrites
Localized Ca2+ signalling in the spines and dendrites of a Purkinje cell.
Panel a represents a region of the dendritic tree of a rat Purkinje cell, with the stimulus electrode on the right-hand side. When the parallel fibres were stimulated, Ca2+ signals were recorded either in the spines (1, 2 and 3) or in the dendrite (4). At low stimulus intensities (five stimuli; panel b), Ca2+ signals were restricted to the spines, whereas at higher stimulus intensity (12 stimuli; panel c), the Ca2+ spread into the dendrite. When caged inositol 1,4,5-trisphosphate (InsP3) was photolysed in a local region (the circle in panel d), there was a large elevation of Ca2+ that spread into neighbouring spines and dendrites (panel e). Reproduced by permission from Macmillan Publishers Ltd: Nature, Finch, E.A. and Augustine, G.J. (1998) Local calcium signalling by inositol 1,4,5-trisphosphate in Purkinje cell dendrites. 396:753–756. Copyright (1998); http://www.nature.com; see Finch and Augustine 1998.