VISIT IN TUBINGEN. The retinal preparation process 1. Removing the eye cup of rat 2. Cut the eye cap...

VISIT IN TUBINGEN

The retinal preparation process1. Removing the eye cup of rat

2. Cut the eye cap along the ora serrata

3. Dissect the retina for three segments that will be recorded

4. Loosen the neural retina from the sclera and transfer it to the recording field of the MEA

The retinal preparation process

The perforated MEA

Improve retina - electrodes contact.

Measure the ganglion cell activity.

The perforated MEA setup

The improved contact achieved by applying a negative pressure fro underneath the MEA

MCS system

Amplifier and data acquisition.

MEAs.Light sources to

stimulate the retina.Perfusion setup.

STIMULUS OF UNIFORMLIGHT

Light intensity of 3.6klux

Cycle time

•Total time of 30 sec

•TP=time of pulse

•f= frequency.

The f and TP values

5ms50ms100ms500ms

0.25Hz

0.5Hz

1Hz

5Hz

10Hz

20Hz

The signal processing block diagram

FFT TRANSFORMATION

ROW ELECTRODE FILTER

200Hz-3kHzreconstruction

Frequency

space

Frequency

space

(peak detector)

Level filter

50mv

Time space

Process the date )frequency, number of AP, width of the

respond …(

Compare between 50,100,500 ms pulse at 0.5Hz from one electrode number 47

0 1 2 3 4 5 6 7 8 9 10-500

0

500

time [sec]

volta

getime space

0 1 2 3 4 5 6 7 8 9 10-500

0

500

time [sec]

volta

ge

time space

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

Frequency space

-5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 50000

5

10x 10

6m

ag

-5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 50000

2

4x 10

6

mag

-5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 50000

1

2x 10

6

mag

freq [Hz]

-100 0 100 200 300 400 500 600 700 800 9000

5

10x 10

6m

ag

-100 0 100 200 300 400 500 600 700 800 9000

2

4x 10

6

mag

-100 0 100 200 300 400 500 600 700 800 9000

1

2x 10

6

mag

freq [Hz]

Frequency space zoom in

Frequency space filtered

-3000 -2000 -1000 0 1000 2000 30000

5

10x 10

4

-3000 -2000 -1000 0 1000 2000 30000

5

10x 10

4

-3000 -2000 -1000 0 1000 2000 30000

5

10x 10

4

freq [Hz]

Reconstructed signal 50,100,500 mswith peak level at 50mV

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

0 1 2 3 4 5 6 7 8 9 10-100

0

100

time [sec]

volta

ge

50ms action potential counter

0 1 2 3 4 5 6 7 8 9 10-150

-100

-50

0

50

100

150

200

250

time [sec]

volta

ge

100ms action potential counter

0 1 2 3 4 5 6 7 8 9 10-150

-100

-50

0

50

100

150

200

250

time [sec]

volta

ge

500ms action potential counter

0 1 2 3 4 5 6 7 8 9 10-100

-50

0

50

100

150

200

250

time [sec]

volta

ge

50ms Action potential frequency

0 1 2 3 4 5 6 7 8 9 10-100

-50

0

50

100

150

time [sec]

freq

uenc

y[A

P/s

ec]

100ms Action potential frequency

0 1 2 3 4 5 6 7 8 9 10-100

-50

0

50

100

150

time [sec]

freq

uenc

y[A

P/s

ec]

500ms Action potential frequency

0 1 2 3 4 5 6 7 8 9 10-100

-50

0

50

100

150

time [sec]

freq

uenc

y[A

P/s

ec]

0 1 2 3 4 5 6 7 8 9 10-500

0

500

time [sec]

volta

getime space

0 1 2 3 4 5 6 7 8 9 10-500

0

500

time [sec]

volta

ge

time space

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

Compare between 50,100,500 ms pulse at 0.25Hz from one electrode number 47

-5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 50000

2

4x 10

6m

ag

-5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 50000

1

2x 10

6

mag

-5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 50000

1

2x 10

6

mag

freq [Hz]

Frequency space

-100 0 100 200 300 400 500 600 700 800 9000

2

4x 10

6m

ag

-100 0 100 200 300 400 500 600 700 800 9000

1

2x 10

6

mag

-100 0 100 200 300 400 500 600 700 800 9000

1

2x 10

6

mag

freq [Hz]

Frequency space zoom in

-3000 -2000 -1000 0 1000 2000 30000

5

10x 10

4

-3000 -2000 -1000 0 1000 2000 30000

5

10x 10

4

-3000 -2000 -1000 0 1000 2000 30000

5

10x 10

4

freq [Hz]

Frequency space filtered

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

0 1 2 3 4 5 6 7 8 9 10-200

0

200

time [sec]

volta

ge

Reconstructed signal 50,100,500 mswith peak level at 50mV

0 1 2 3 4 5 6 7 8 9 10-150

-100

-50

0

50

100

150

200

250

time [sec]

volta

ge50ms action potential counter

0 1 2 3 4 5 6 7 8 9 10-150

-100

-50

0

50

100

150

200

250

time [sec]

volta

ge100ms action potential counter

0 1 2 3 4 5 6 7 8 9 10-200

-150

-100

-50

0

50

100

150

200

250

time [sec]

volta

ge500ms action potential counter

0 1 2 3 4 5 6 7 8 9 10-200

-150

-100

-50

0

50

100

150

time [sec]

freq

uenc

y[A

P/s

ec]

50ms Action potential frequency

0 1 2 3 4 5 6 7 8 9 10-200

-150

-100

-50

0

50

100

150

200

time [sec]

freq

uenc

y[A

P/s

ec]

100ms Action potential frequency

0 1 2 3 4 5 6 7 8 9 10-200

-150

-100

-50

0

50

100

150

200

time [sec]

freq

uenc

y[A

P/s

ec]

500ms Action potential frequency

The total result of all the electrodestimulus of 0.5Hz 50ms

0 5 10 15 20 25 30 350

1000

2000

3000

4000

5000

6000

7000Total number of action potential

time[sec]

Tot

al n

umbe

r of

act

ion

pote

ntia

l

Number of action potential at 10ms stimulus of 0.5Hz 50ms

0 5 10 15 20 25 30 350

2

4

6

8

10

12

14

16

18

20number of AP)time(

time[sec]

num

ber

of a

ctio

n po

tent

ial a

t 10

ms

Action potential frequency )calculated at

100ms( stimulus of 0.5Hz 50ms

0 5 10 15 20 25 30 350

200

400

600

800

1000

1200action potential frequency

time [sec]

freq

uenc

y[A

P/s

ec]

The total result of all the electrodestimulus of 0. 5Hz 100ms

0 5 10 15 20 25 30 350

1000

2000

3000

4000

5000

6000Total number of action potential

time[sec]

Tot

al n

umbe

r of

act

ion

pote

ntia

l

Number of action potential at 10ms stimulus of 0.5Hz 100ms

0 5 10 15 20 25 30 350

2

4

6

8

10

12

14

16

18

20number of AP/10ms)time(

time[sec]

num

ber

of a

ctio

n po

tent

ial a

t 10

ms

Action potential frequency )calculated at

100ms( stimulus of 0.5Hz 100ms

0 5 10 15 20 25 30 350

100

200

300

400

500

600

700

800

900

1000action potential frequency

time [sec]

freq

uenc

y[A

P/s

ec]

The total result of all the electrodestimulus of 0.5Hz 500ms

0 5 10 15 20 25 30 350

500

1000

1500

2000

2500

3000

3500

4000

4500Total number of action potential

time[sec]

Tot

al n

umbe

r of

act

ion

pote

ntia

l

Number of action potential at 10ms stimulus of 0.5Hz 500ms

0 5 10 15 20 25 30 350

2

4

6

8

10

12number of AP/10ms)time(

time[sec]

num

ber

of a

ctio

n po

tent

ial a

t 10

ms

Action potential frequency )calculated at 100ms( stimulus of 0.5Hz 500ms

0 5 10 15 20 25 30 350

100

200

300

400

500

600

700

800action potential frequency

time [sec]

freq

uenc

y[A

P/s

ec]

Zoom in at the stimulus of 0.5Hz 500 ms pulse counter.

0 1 2 3 4 5 6 70

500

1000

1500

2000

2500Total number of action potential

time[sec]

Tot

al n

umbe

r of

act

ion

pote

ntia

l

Zoom in at the stimulus of 0.5Hz 500 ms )number of pulse at 10ms (

0 1 2 3 4 5 6 70

2

4

6

8

10

12number of AP/10ms)time(

time[sec]

num

ber

of a

ctio

n po

tent

ial a

t 10

ms

0 1 2 3 4 5 6 70

100

200

300

400

500

600

700

800action potential frequency

time [sec]

freq

uenc

y[A

P/s

ec]

Zoom in at the stimulus of 0.5Hz 500 ms )frequency (

Experiment in chicken retina

Focusing image from computer display on the retina.

the space and time frequency can be controlled.

the stimulus is from the bottom

The optic setup

45 d mirror. Lance to focus the

image. Mechanical setup. display that radiate

the image.

Movie of the experiment

The buffer components ratchicken

mMg/molg/1litermMg/molg/1liter

NaCl12058.447.01281005.84

KCl574.560.372860.4476

NaHCO33084.012.5203302.52

GLUKOSE15180.162.7024509.01

L-GLUTAMAT0.2169.10.03382

MgCl2 6H2O1203.30.203320.493

PHENOLROT1ml

ph7.57.5

OSMOLARIT333326-328

NaH2PO4)1H2O(10.138

CaCl2)2H20(10.147

The retina preparation