MED64 Application Specialists
A complete, easy-to-use Multi-Electrode Array based solution for
advanced in vitro multi-site extracellular electrophysiology.
home  |   products  |   applications  |   resources  |   support  |   contact
Applications
Search Our Site:
  Synaptic Activity
  Biological Rythms
  Pharmacology and Drug Testing
  Unit and Network Activity
  Muscle Propagation and Pacing
  Combining with Other Equipment

  Preparation Based Applications

Muscle Propagation and Pacing

Exampel 1: Spontaneous and Stiimulus-evoked pacing Responses in Primary Myocyte Cultures

A.Fluorescence micrograph of myocytes cultured on a MED-P545A probe (450 µm inter-electrode spacing)
B. Spontaneous responses obtained from 64 electrodes. Calibration: 0.5mV, 10ms
C.Pacing responses were evoked by electric stimulation using two electrodes on the MED probe (arrow). Calibration: 0.5mV, 10ms
D.Phase map of the pacing activity. Each contour shows the latency (ms) of the responses evoked by stimulation.

Courtesy of Drs. Lee and Kodama, Nagoya University, Japan

 

---------------------------------------------------------------------------------------------------------------------------------------

Example 2: Pacing on rat acute atrial tissue

[Left] Micrograph of a slice from rat atrial tissue on MED-P545A probe (450 µm inter-polar distance
[Right] Pacing responses were evoked by electric stimulation to the two electrodes on MED probe.

Propagation of the pacing activity. Each time frame shows the computed two dimensional field potential distribution over time. The times after the stimulation are shown in each panel. Positive potentials are white and negatives are black.

Courtesy of Dr. H.Yeh,
Mackay Memorial Hospital, Taiwan

---------------------------------------------------------------------------------------------------------------------------------------

Example 3: Recordings from Smooth Muscle

Spontaneous potentials exhibited by a smooth muscle (circular & longitudinal) preparation obtained from a small segment of guinea pig intestine. The preparation was placed on a MED64 electrode array (450 µm inter-electrode spacing and held down using netting and slice anchors (as typically done with brain slices).

(a) This series of frames illustrates the spread of pacemaker activity seen along circular muscle in the presence of 1 µMNifedipineand 250 nMTTX. The voltages recorded at each electrode are pseudo-color coded (scale at right) and oriented as shown in the first panel. The frames were taken 50 msec apart, and are displayed temporally from left to right for the top, and then the bottom rows. As shown, the peak negativities (yellow) spread along the orientation of the circular muscle (left to right), which was preferentially oriented to be in closest contact with the electrode array.

(b) Latency maps of the peak negativity (left graph) and positivity(right graph) also illustrate the phase differences observed in spontaneous pacemaker activity. The phase map of the negative peak is, as shown in a, consistent with the spread of pacemaker activity along the direction in which the circular muscle is oriented. The map of the positive peak is consistent with this, but also suggests spread along the direction (bottom to top) of the longitudinal muscle.

Courtesy of Dr. Nakayama, Dept. of Cell Physiology, Graduate school of medicine, Nagoya University, Japan

Home | Products | Applications | Resources | Support | Site Map | Contact
Copyright © 1995-2010 Alpha Med Sciences.
Web Hosting Provided by EPhost