Excitabilidade Elétrica das Células

Excitabilidade Eltrica das Clulas

Eletrofisiologia: Pr-HistriaLuigi Galvani: 1737-1798

Excitabilidade Eltrica das ClulasOscilaes da diferena de potencial eltrico, em escala de tempo de ms, associadas transduo sensorial em receptores, transmisso de informaes em neurnios e clulas musculares e transmisso de informao entre clulas, nas sinapsesPotencial de ao Resposta tudo ou nadaPotencial gerador.

Excitabilidade: Repostas graduadas e potenciais de ao

Potencial de ao como resposta local, registrada no compartimento intracelular

POTENCIAL DE AO resposta local propagao

Potencial de ao: Circuito eltrico equivalente para a membranaCmgClgKicexgNai

Potencial de ao: Fenomenologia da resposta local

Excitabilidade: potenciais de ao

O Potencial de AoReverso da polaridadeLimiarPs-potencial

Potenciais de ao: Limiar

Potenciais de ao: Perodos refratrios

Mecanismos inicos da resposta local

Oscilaes da diferena de potencial eltrico nas clulas so determinados primariamente pela transferncia de carga pelo fluxo de ons atravs de canais[K]=110mM[Na+]=10mM[Na+]=135mM[K+]= 4mM--++

Gnese dos Potenciais de membrana (Medidas intracelulares no axnio gigante de lula)

Mas a membrana permevel a vrios ons....Equao de Hodgkin-Katz-Goldman, considerados apenas os efeitos de ons monovalentes

Fixao de voltagem 10mmVcVmi

Correntes inicas que causam o potencial de ao em axnios

Condutncias dependentes de voltagem em axnios

Esquemas cinticos para os canais Canais para Na+Canais para K+FAFAI

Cinticas das condutncias: a potssio

Cinticas das condutncias: sdio

K(Vm,t)

Relaes I-V

Sheet1

Na1000ka15

gca10Era-100

Vha-40

Nb1000kb5

gcb10Erb50

Vhb-100

A.C.Cassola v.0, 04/2000

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Sheet1

6.53E-044.54E-05

9.11E-041.23E-04

1.27E-033.35E-04

1.77E-039.11E-04

2.47E-032.47E-03

3.45E-036.69E-03

4.80E-031.80E-02

6.69E-034.74E-02

9.32E-031.19E-01

1.30E-022.69E-01

1.80E-025.00E-01

2.49E-027.31E-01

3.44E-028.81E-01

4.74E-029.53E-01

6.50E-029.82E-01

8.84E-029.93E-01

1.19E-019.98E-01

1.59E-019.99E-01

2.09E-011.00E+00

2.69E-011.00E+00

3.39E-011.00E+00

4.17E-011.00E+00

5.00E-011.00E+00

5.83E-011.00E+00

6.61E-011.00E+00

7.31E-011.00E+00

7.91E-011.00E+00

8.41E-011.00E+00

8.81E-011.00E+00

9.12E-011.00E+00

9.35E-011.00E+00

9.53E-011.00E+00

9.66E-011.00E+00

9.75E-011.00E+00

9.82E-011.00E+00

9.87E-011.00E+00

9.91E-011.00E+00

9.93E-011.00E+00

9.95E-011.00E+00

9.97E-011.00E+00

9.98E-011.00E+00

9.98E-011.00E+00

9.99E-011.00E+00

9.99E-011.00E+00

9.99E-011.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

1.00E+001.00E+00

Vm(mV)

Po

Sheet2

Vm(mV)Po(V)G(V)IiVm(mV)Po(V)G(V)Ii

-1500.00065296530-3.26E-10-1500.00004539790-9.08E-11

-1450.00091105120-4.10E-10-1450.00012339460-2.41E-10

-1400.00127101630-5.08E-10-1400.00033535010-6.37E-10

-1350.00177295460-6.21E-10-1350.00091105120-1.69E-09

-1300.00247262320-7.42E-10-1300.00247262320-4.45E-09

-1250.00344745130-8.62E-10-1250.00669285090.0000000001-1.17E-08

-1200.00480475290-9.61E-10-1200.017986210.0000000002-3.06E-08

-1150.00669285090.0000000001-1.00E-09-1150.04742587320.0000000005-7.83E-08

-1100.00931595930.0000000001-9.32E-10-1100.1192029220.0000000012-1.91E-07

-1050.01295372750.0000000001-6.48E-10-1050.26894142140.0000000027-4.17E-07

-1000.017986210.00000000020.00E+00-1000.50.000000005-7.50E-07

-950.02492442660.00000000021.25E-09-950.73105857860.0000000073-1.06E-06

-900.03444519570.00000000033.44E-09-900.8807970780.0000000088-1.23E-06

-850.04742587320.00000000057.11E-09-850.95257412680.0000000095-1.29E-06

-800.06496916910.00000000061.30E-08-800.982013790.0000000098-1.28E-06

-750.08839967720.00000000092.21E-08-750.99330714910.0000000099-1.24E-06

-700.1192029220.00000000123.58E-08-700.99752737680.00000001-1.20E-06

-650.15886910490.00000000165.56E-08-650.99908894880.00000001-1.15E-06

-600.20860852730.00000000218.34E-08-600.99966464990.00000001-1.10E-06

-550.26894142140.00000000271.21E-07-550.99987660540.00000001-1.05E-06

-500.33924363120.00000000341.70E-07-500.99995460210.00000001-1.00E-06

-450.41742979350.00000000422.30E-07-450.99998329860.00000001-9.50E-07

-400.50.0000000053.00E-07-400.99999385580.00000001-9.00E-07

-350.58257020650.00000000583.79E-07-350.99999773970.00000001-8.50E-07

-300.66075636880.00000000664.63E-07-300.99999916850.00000001-8.00E-07

-250.73105857860.00000000735.48E-07-250.99999969410.00000001-7.50E-07

-200.79139147270.00000000796.33E-07-200.99999988750.00000001-7.00E-07

-150.84113089510.00000000847.15E-07-150.99999995860.00000001-6.50E-07

-100.8807970780.00000000887.93E-07-100.99999998480.00000001-6.00E-07

-50.91160032280.00000000918.66E-07-50.99999999440.00000001-5.50E-07

00.93503083090.00000000949.35E-0700.99999999790.00000001-5.00E-07

50.95257412680.00000000951.00E-0650.99999999920.00000001-4.50E-07

100.96555480430.00000000971.06E-06100.99999999970.00000001-4.00E-07

150.97507557340.00000000981.12E-06150.99999999990.00000001-3.50E-07

200.982013790.00000000981.18E-062010.00000001-3.00E-07

250.98704627250.00000000991.23E-062510.00000001-2.50E-07

300.99068404070.00000000991.29E-063010.00000001-2.00E-07

350.99330714910.00000000991.34E-063510.00000001-1.50E-07

400.99519524710.000000011.39E-064010.00000001-1.00E-07

450.99655254870.000000011.45E-064510.00000001-5.00E-08

500.99752737680.000000011.50E-065010.000000010.00E+00

550.99822704540.000000011.55E-065510.000000015.00E-08

600.99872898370.000000011.60E-066010.000000011.00E-07

650.99908894880.000000011.65E-066510.000000011.50E-07

700.99934703470.000000011.70E-067010.000000012.00E-07

750.99953204330.000000011.75E-067510.000000012.50E-07

800.99966464990.000000011.80E-068010.000000013.00E-07

850.99975968830.000000011.85E-068510.000000013.50E-07

900.99982779740.000000011.90E-069010.000000014.00E-07

950.99987660540.000000011.95E-069510.000000014.50E-07

1000.99991158080.000000012.00E-0610010.000000015.00E-07

1050.99993664330.000000012.05E-0610510.000000015.50E-07

1100.99995460210.000000012.10E-0611010.000000016.00E-07

1150.99996747060.000000012.15E-0611510.000000016.50E-07

1200.99997669140.000000012.20E-0612010.000000017.00E-07

1250.99998329860.000000012.25E-0612510.000000017.50E-07

1300.99998803290.000000012.30E-0613010.000000018.00E-07

1350.99999142510.000000012.35E-0613510.000000018.50E-07

1400.99999385580.000000012.40E-0614010.000000019.00E-07

1450.99999559750.000000012.45E-0614510.000000019.50E-07

1500.99999684550.000000012.50E-0615010.000000011.00E-06

Vm(mV)

I(Amp)

Peak Current

-1.50E+02

-1.50E+02

-1.45E+02

-1.45E+02

-1.40E+02

-1.40E+02

-1.35E+02

-1.35E+02

-1.30E+02

-1.30E+02

-1.25E+02

-1.25E+02

-1.20E+02

-1.20E+02

-1.15E+02

-1.15E+02

-1.10E+02

-1.10E+02

-1.05E+02

-1.05E+02

-1.00E+02

-1.00E+02

-9.50E+01

-9.50E+01

-9.00E+01

-9.00E+01

-8.50E+01

-8.50E+01

-8.00E+01

-8.00E+01

-7.50E+01

-7.50E+01

-7.00E+01

-7.00E+01

-6.50E+01

-6.50E+01

-6.00E+01

-6.00E+01

-5.50E+01

-5.50E+01

-5.00E+01

-5.00E+01

-4.50E+01

-4.50E+01

-4.00E+01

-4.00E+01

-3.50E+01

-3.50E+01

-3.00E+01

-3.00E+01

-2.50E+01

-2.50E+01

-2.00E+01

-2.00E+01

-1.50E+01

-1.50E+01

-1.00E+01

-1.00E+01

-5.00E+00

-5.00E+00

0.00E+00

0.00E+00

5.00E+00

5.00E+00

1.00E+01

1.00E+01

1.50E+01

1.50E+01

2.00E+01

2.00E+01

2.50E+01

2.50E+01

3.00E+01

3.00E+01

3.50E+01

3.50E+01

4.00E+01

4.00E+01

4.50E+01

4.50E+01

5.00E+01

5.00E+01

5.50E+01

5.50E+01

6.00E+01

6.00E+01

6.50E+01

6.50E+01

7.00E+01

7.00E+01

7.50E+01

7.50E+01

8.00E+01

8.00E+01

8.50E+01

8.50E+01

9.00E+01

9.00E+01

9.50E+01

9.50E+01

1.00E+02

1.00E+02

1.05E+02

1.05E+02

1.10E+02

1.10E+02

1.15E+02

1.15E+02

1.20E+02

1.20E+02

1.25E+02

1.25E+02

1.30E+02

1.30E+02

1.35E+02

1.35E+02

1.40E+02

1.40E+02

1.45E+02

1.45E+02

1.50E+02

1.50E+02

-3.26E-10

-9.08E-11

-4.10E-10

-2.41E-10

-5.08E-10

-6.37E-10

-6.21E-10

-1.69E-09

-7.42E-10

-4.45E-09

-8.62E-10

-1.17E-08

-9.61E-10

-3.06E-08

-1.00E-09

-7.83E-08

-9.32E-10

-1.91E-07

-6.48E-10

-4.17E-07

0.00E+00

-7.50E-07

1.25E-09

-1.06E-06

3.44E-09

-1.23E-06

7.11E-09

-1.29E-06

1.30E-08

-1.28E-06

2.21E-08

-1.24E-06

3.58E-08

-1.20E-06

5.56E-08

-1.15E-06

8.34E-08

-1.10E-06

1.21E-07

-1.05E-06

1.70E-07

-1.00E-06

2.30E-07

-9.50E-07

3.00E-07

-9.00E-07

3.79E-07

-8.50E-07

4.63E-07

-8.00E-07

5.48E-07

-7.50E-07

6.33E-07

-7.00E-07

7.15E-07

-6.50E-07

7.93E-07

-6.00E-07

8.66E-07

-5.50E-07

9.35E-07

-5.00E-07

1.00E-06

-4.50E-07

1.06E-06

-4.00E-07

1.12E-06

-3.50E-07

1.18E-06

-3.00E-07

1.23E-06

-2.50E-07

1.29E-06

-2.00E-07

1.34E-06

-1.50E-07

1.39E-06

-1.00E-07

1.45E-06

-5.00E-08

1.50E-06

0.00E+00

1.55E-06

5.00E-08

1.60E-06

1.00E-07

1.65E-06

1.50E-07

1.70E-06

2.00E-07

1.75E-06

2.50E-07

1.80E-06

3.00E-07

1.85E-06

3.50E-07

1.90E-06

4.00E-07

1.95E-06

4.50E-07

2.00E-06

5.00E-07

2.05E-06

5.50E-07

2.10E-06

6.00E-07

2.15E-06

6.50E-07

2.20E-06

7.00E-07

2.25E-06

7.50E-07

2.30E-06

8.00E-07

2.35E-06

8.50E-07

2.40E-06

9.00E-07

2.45E-06

9.50E-07

2.50E-06

1.00E-06

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Sheet7

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Sheet8

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Sheet9

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Sheet10

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Sheet11

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Sheet12

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Sheet13

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Sheet14

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Sheet15

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Sheet16

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Modelo de Hodgkin-HuxleyCondutncia a K+

Modelo de Hodgkin-HuxleyCondutncia a Na+Ativao (m)Inativao (h)

Modelo de Hodgkin-Huxley

Prmio Nobel de 1963Alan LLoyd Hodgkin1914-1998Andrew Fielding Huxley1917-John Carew Eccles1903-1997

Super-famlia dos canais dependentes de voltagem

Gating do Canal

Ativao Inativao

Filogenia dos KV

Canal para Na - filogenia

Excitabilidade Elétrica das Células

Documents

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