The effects of fear conditioning on cerebellar LTP and LTD
Date
2007-09-19Abstract
Long-term potentiation (LTP) and depression (LTD) at parallel fibre-Purkinje cell
synapses have been described in vitro in the cerebellar cortex, but the
physiological roles of these two forms of plasticity have not been well defined.
Here we show that, in cerebellar slices taken from rats that had undergone fear
conditioning, there was a significant occlusion of electrically induced LTP at
parallel fibre-Purkinje cell synapses. This effect was long-lasting and related
to associative processes, as LTP was not occluded in unpaired animals. Notably,
in conditioned animals the LTP-inducing protocol produced LTD in some cells
instead of LTP. Conversely, synaptic depression induced by conjunctive
stimulation of parallel fibers and climbing fibres was impaired in tissue taken
immediately following aversive stimulation in both paired and unpaired subjects.
This effect was not, however, long-lasting as the incidence and extent of LTD
returned to normal levels 24 h after behavioural testing. These findings suggest
that LTP takes part in the mechanisms underlying aversive associative memories in
the cerebellum.
Description
Citation : Zhu, L. et al. (2007) The effects of fear conditioning on cerebellar LTP and LTD. The European journal of neuroscience, 26 (1), pp. 219-227
ISSN : 0953-816X
Research Institute : Leicester Institute for Pharmaceutical Innovation - From Molecules to Practice (LIPI)
Peer Reviewed : Yes