Table I.
Contact lens protection against UVA-induced loss of pyridine nucleotides in rabbit lens in vivo*
| Pyridine nucleotide concentrations (% loss, compared to control) | |||||||
|---|---|---|---|---|---|---|---|
| A | NADH | ||||||
| no lens (% loss) | senofilcon A (% loss) | protection (%) | p | lotrafilcon A (% loss) | protection (%) | p | |
| AC | 13±19 | 6±24 | 54 | >0.1 | 10±17 | 23 | >0.1 |
| EC | 11±15 | 16±18 | 0 | >0.1 | 15±11 | 0 | >0.1 |
| N | 53±13 | 0±4 | 100 | <0.0001 | 44±22 | 17 | >0.1 |
| PC | 16±17 | 0±14 | 100 | >0.05 | 23±12 | 0 | >0.1 |
| B | NAD+ | ||||||
| AC | 46±18 | 0±1 | 100 | <0.001 | 48±35 | 0 | >0.1 |
| EC | 22±14 | 5±3 | 77 | <0.05 | 24±12 | 0 | >0.1 |
| N | 56±14 | 4±17 | 93 | <0.001 | 54±11 | 4 | >0.1 |
| PC | 50±25 | 10±16 | 80 | <0.05 | 43±28 | 14 | >0.1 |
| C | NADPH | ||||||
| AC | 62±17 | 25±29 | 60 | <0.01 | 65±8 | 0 | >0.1 |
| EC | 44±23 | 34±31 | 23 | >0.1 | 58±14 | 0 | >0.1 |
| N | 52±12 | 26±10 | 50 | <0.01 | 58±15 | 0 | >0.1 |
| PC | 47±19 | 18±7 | 62 | <0.05 | 55±22 | 0 | >0.1 |
| D | NADP+ | ||||||
| AC | 75±11 | 6±41 | 92 | <0.001 | 60±7 | 20 | >0.1 |
| EC | 52±4 | 22±15 | 58 | <0.0001 | 50±18 | 4 | >0.1 |
| N | 71±8 | 38±28 | 46 | <0.01 | 74±4 | 0 | >0.1 |
| PC | 63±14 | 19±23 | 70 | <0.001 | 64±8 | 0 | >0.1 |
Eyes of anesthetized rabbits were exposed to UVA light for 1 hour (monochromatic 365 nm light, 100 mW/cm2 on the cornea) with and without the presence of a senofilcon A or lotrafilcon A contact lens. The rabbits were euthanized immediately after the exposure, and the isolated lenses frozen in dry ice and divided into anterior cortex (AC), equatorial cortex (EC), nucleus (N) and posterior cortex (PC) for analysis. In each case, the contralateral lens served as the control. Results (% loss, compared to control) are expressed as means ± S.D; n=10 for no contact lens, n=3 for a senofilcon A contact lens and n=4 for a lotrafilcon A contact lens. Percent protection is calculated as %loss (no contact lens) − %loss (contact lens) / %loss (no contact lens) × 100. Mean control values (nm/g wet wt.) for the four nucleotides ranged from 861(N) to 1384(EC) for NAD+, 384(EC) to 733(N) for NADH, 11(N) to 31(EC) for NADP+ and 6(N) to 39(EC) for NADPH.