Table 1

Parameters of the model. Values used in the fits illustrated in Figs 2 and 3 are compared with the generic values for macaque reported in [3].

Parameter

Description

Generic macaque cone [3]

Human cone (Fig. 2)

Ground squirrel (Fig. 3)

Units

τ_R

Time constant of R* inactivation

3.4

3.4

3.0

ms

τ_E

Time constant of E* inactivation

8.7

9.6

13

ms

τ_D

Time constant of cGMP hydrolysis in darkness

360

360

60

ms

k_β

Coupling gain from light intensity to rate of hydrolysis of cGMP

1.6·10^-4

10^-4

(ms)^-1 td^-1

2.1·10^-7

(ms)^-1 (isom/s)^-1

n_X

Apparent Hill coefficient of CNG channel activation

1

1

1.7

-

τ_Ca

Time constant of Ca²⁺ extrusion

3

3

4.8

ms

n_cyc

Hill coefficient of GC activation

4

4

3.2

-

a_cyc

Scaling constant of GC activation

9·10^-2

9·10^-2

3.7·10^-2

-

τ_m

Outer segment capacitive time constant

< 4

2.3

2.3

ms

t_delay

Delay time

< 3

1.3

2.2

ms

van Hateren and Lamb BMC Neuroscience 2006 7:34   doi:10.1186/1471-2202-7-34