Experiment-based Applications

Synaptic Plasticity

Single Unit Activity

Rhythmic Activity

Muscle Propagation
and Pacing

QT Prolongation

Pharmacology and
Drug Testing

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Preparation-Based Applications

MED64 APPLICATIONS

Synaptic Plasticity

Example 1: Long term potentiation in acute hippocampus slices

• Simply place the slice on the MED probe and you are ready to record! (No need for pullers, manipulators or glass microelectrodes).
• No need for a special shielded environment. Make low-noise recordings consistently every day without a Faraday cage.
• Stimuli can be delivered from all 64 electrodes (up to 2 at a time). Look for the best stimulation point easily by using the software controller.
• Conduct your experiments and perform on-line analysis using MED64 Mobius software.

[Left] Micrograph of a C57BL6 mouse hippocampal slice placed on a MED probe. 
[Right] fEPSPs were elicited with a single pulse stimulus at electrode 21 (marked in blue) Responses were recorded at the other 63 electrodes.

[Right] The time course of the slope (10-40%) and minimum amplitude of the fEPSP recorded at electrode 29 (marked in red on the above micrograph). The same analysis is performed at all other 63 electrodes.

Example 2: Longevity of cultured hippocampal slices

A. Hippocampal slice cultured on a MED probe (MED-P515A, 150µm inter-polar distance)

B. Field EPSPs evoked by Schaffer/Commissural stimulation were recorded at CA1 before and after tetanic stimulation.

C. Summary graph showing the stability of LTP over several days. The amplitude of the fEPSP (calculated as a percentage of averaged baseline values; means ±SEM., n=8) , is shown for the control and potentiated pathways. Arrows indicate the time of tetanus stimulation.

D.LTP amplitude was averaged over a 10min period at 1h, 24h, and 48h after tetanus stimulation, and was expressed as percentage of baseline values.

Shimono K et al., Neural Plasticity 2002, 9(4) 249-254

Example 3: Continuous two-dimensional current source density analysis of an evoked response

A. Placement of an 8 x 8 MED64 electrode array, with an interelectrode spacing of 100µm, centered in the apical dendritic field of CA1 in a rat hippocampal slice. 

B. Evoked field EPSP (black) and field EPSC (red) are elicited by a single pulse to the electrode marked in red and measured at the electrode in blue. 

C. The computed continuous two-dimensional current source density plots across all electrodes at specified time points. After an initial response due to the fiber volley, a current sink spreads rapidly through the stratum radiatum zone of field CA1. The sink intensifies and expands over roughly 5ms and then fades, disappearing at about 20ms. The apical sink is accompanied by a field of current source appearing in both the basal dendrites and the stratum lacunosum/moleculare.

K. Shimono et al. Brain Res., 2002, 950(1-2):279-287