ERG recordings from Long-Evans (LE) (n = 7), NIH nude (n = 6), and RD nude rats (no surgery, n = 6; sham, n = 5; transplant, n = 6) at the age of 2.5 to 6 months. Results are presented as mean + SEM. (A) Scotopic response B-wave amplitude: robust response from LE and NIH nude rats but no response from RD nude rats (P < 0.0001). (B) Photopic B-wave: robust responses in LE and NIH nude rats but no response in RD rats (P < 0.05).