Table 2 Parameters obtained from intensity-response relationships.

From: Characterization of zebrafish rod and cone photoresponses

 

Rmax

(pA)

I1/2

(photons μm−2)

Hill coefficient

Sf

(pA photons−1 μm−2)

Fractional Sf

(10−4 photons−1 μm−2)

n

Red-sensitive cones

13 ± 1

1600 ± 400

1.00 ± 0.02

0.011 ± 0.002

8.2 ± 1.4

19

Green-sensitive cones

7.5 ± 0.7

290 ± 50

0.86 ± 0.02

0.038 ± 0.006

62 ± 12

22

Blue-sensitive cones

11.5 ± 0.7

660 ± 60

0.89 ± 0.01

0.020 ± 0.003

17 ± 2

18

UV-sensitive cones*

6.0 ± 0.6

5090 ± 460

(930 ± 80)

0.94 ± 0.02

0.0011 ± 0.0002

(0.0061 ± 0.0011)

2.1 ± 0.3

(12 ± 2)

18

Rods

5.7 ± 0.3

7.3 ± 0.6

1.39 ± 0.04

0.43 ± 0.04

760 ± 70

20

  1. Definition of Rmax and I1/2 are illustrated in Fig. 4a,b for rod data. Sf and Fractional Sf were determined from cells whose photoresponse Rmax was 2.0 pA or larger. Sf is flash sensitivity defined as response amplitude to 1 photon μm−2 flash, which is estimated by dividing the dim flash response amplitude with the flash intensity. Fractional Sf is obtained by dividing Sf with Rmax.
  2. *Sensitivity values for UV-sensitive cones are determined using violet light at 405 nm, which is 44 nm longer than their reported λmax at 361 nm (Allison et al. 2004). Values in parentheses were obtained after the adjustment for the 5.5-fold higher sensitivity at λmax compared to 405 nm.
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