Hippocampal slice transverse

A variety of different types of tissue preparation are used to study neurosecretion and synaptic transmission. A classical preparation is the frog NMJ (discussed below). The brain slice has been used for many years for biochemical studies of CNS metabolism and is a useful preparation for electrophysiological studies of synaptic transmission in the CNS. Slices can be oriented to maintain the local neuronal circuitry and can be thin, 0.3 mm, to minimize anoxia. The transverse hippocampal slice is widely used as an electrophysiological preparation to study synaptic plasticity (see Ch. 53). Primary cultures of neurons from selected CNS areas and sympathetic ganglia are also frequently used. They permit excellent visual identification of individual neurons and control of the extracellular milieu, but the normal neuronal connections are disrupted. 

Fig. 2. Appearance of hippocampal slices from postnatal d 10 rat pups immediately after slicing and after 21 DIV. Transverse slices were immediately prepared (0 DIV) or cultured (21 DIV), Slices were fixed and stained with cresyl violet. The neuronal layers of the dentate gyrus, CAl, CA3, the subiculum, and the entorhinal cortex are evident immediately after slicing. After 21 DIV, CA3, CAl and the dentate gyrus are well preserved whereas the entorhinal cortex and subiculum have degenerated. Neuronal layers in the 2IDIV culture are wider because of the thinning of the slice in vitro. Superior preservation of the slice is indicated by a similar density of staining between the CA3 and CAl pyramidal cell layers or between the upper and lower limbs of the dentate gyrus.

Dingledine, R., Dodd, J., and Kelly, J. S., 1977a, Intracellular recording from pyramidal neurones in the in vivo transverse hippocampal slice,/. Physiol. 269 13-15P. 

Skrede, K. K., and Westgaard, R. H., 1971, The transverse hippocampal slice a well-defined cortical structure maintained in vitro. Brain Res. 35 589-593. 

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