Table 1.
Effect of proparacaine (PPC), tetrodotoxin (TTX), and octyltrimethylammonium bromide (OTAB) on the duration of corneal anesthesia.
| TTX (mM) |
OTAB (mM) |
PPC (mM) |
Block0.5 (min) |
Block2 (min) |
Block<6 (min) |
|---|---|---|---|---|---|
| - | - | 15 | 17 ± 5 | 22 ± 5.3 | 90 ± 24.4 |
| - | 0.5 | 15 | 10 ± 0.1 | 22 ± 2.6 | 52 ± 15.0 |
| 0.1 | - | - | 0 | 0 | 45 ± 29.5 |
| 0.1 | 0.1 | - | 0 | 4 ± 7.8 | 105 ± 30.0 |
| 0.1 | - | 15 | 30 ± 21.6 | 55 ± 30 | 420 ± 69.2*† |
| 0.1 | 0.1 | 15 | 30 ± 20 | 64 ± 28.8 | 417 ± 5.0*† |
| 1 | - | - | 0 | 13 ± 15.2 | 105 ± 90.0 |
| 1 | 1 | - | 10 ± 14.1 | 20 ± 14.8 | 195 ± 57.4 |
| 1 | - | 15 | 75 ± 30* | 179 ± 21.2 *† | 345 ± 57.4*† |
| 1 | 1 | 15 | 90 ± 34.6* | 180 ± 20.7 *† | 345 ± 57.4*† |
| 3 | - | - | 10 ± 11.7 | 66 ± 55.7 | 210 ± 34.6 |
| 3 | 3 | - | 25 ± 10 | 85 ± 93.4 | 297 ± 5.0* |
| 3 | - | 15 | 90 ± 34.6* | 180 ± 17.2 *† | 375 ± 30.0*† |
| 3 | 3 | 15 | 105 ± 57.4* | 246 ± 134.4 *† | 615 ± 172.3*†‡ |
| 6 | - | - | 7 ± 9.5 | 57 ± 35.45 | 225 ± 90.0 |
| 6 | 6 | - | 75 ± 30 | 64 ± 15.3 | 270 ± 60.0* |
| 6 | - | 15 | 75 ± 30* | 141 ± 18.6 * | 390 ± 34.6*† |
| 6 | 6 | 15 | 82 ± 45* | 163 ± 61.3 *† | 585 ± 157*†‡ |
Block0.5, 2, <6: duration of absent blink response when the cornea was probed with filament length of 0.5 cm (complete blocks), 2 cm (dense blocks) and 6 cm (any degree of block; time to block resolution) respectively. Data are means ± SD, n=4. Groups were compared using one-way ANOVA with Bonferroni post hoc test.
*
p< 0.05 compared to 15 mM proparacaine,
†
p < 0.05, compared with rats administered TTX only within each TTX concentration group,
‡
p < 0.05, compared with rats co-administered TTX and proparacaine within each TTX concentration group.