Table 2:
Serum and Thyroid Gland MMI levels and Gland Hormone Concentrations
| MMI exposure duration/doses (ppm) 4 day | Serum MMI (ng/ml) | Gland MMI (ng/g) | Hormone Concentrations in the Thyroid Gland (ng/mg) | ||||
|---|---|---|---|---|---|---|---|
| MIT | DIT | T3 | rT3 | T4 | |||
| 0 | <0.381 | <251 | 28 (6) | 617 (73) | 36 (4) | 5 (0.6) | 215 (23) |
| 3 | 37 (7) | 1,698 (350) | 25 (6) | 485 (92) | 31 (8) | 5 (0.9) | 190 (50) |
| 30 | 512 (59) | 3,135 (381) | 5 (1) * | 76 (19) * | 3 (0.6) * | 0.8 (0.2) * | 20 (5) * |
| 200 | 2,376 (222) | 3,038 (504) | 9 (3) * | 163 (46) * | 7 (2) * | 1 (0.3) * | 45 (13) * |
| 7 day | |||||||
| 0 | <0.381 | <251 | 23 (7) | 653 (147) | 29 (8) | 9 (2) | 208 (40) |
| 3 | 47 (8) | 1,850 (350) | 14 (0.3) | 266 (54) * | 18 (3) | 3 (0.4) * | 82 (16) * |
| 30 | 517 (64) | 2,871 (430) | 4 (1) * | 41 (18) * | 2 (0.8) * | 0.5 (0.1) * | 12 (4) * |
| 200 | 2,249 (264) | 3,110 (227) | 1 (0.2) * | 12 (3) * | 0.6 (0.1) * | 0.2 (0.1) * | 5 (1) * |
| 14 day | |||||||
| 0 | <0.381 | <251 | 17 (4) | 415 (79) | 32 (7) | 6 (1) | 154 (29) |
| 3 | 24 (6) | 589 (144) | 8 (2) * | 146 (40) * | 18 (2) | 4 (0.4) * | 89 (10) * |
| 30 | 415 (47) | 2,266 (150) | 2 (0.3) * | 13 (2) * | 1 (0.3) * | 0.4 (0.1) * | 7 (1) * |
| 200 | 2,448 (192) | 3,263 (345) | 0.7 (0.1) * | 6 (2) * | 0.4 (0.1) * | 0.1 (0.03) * | 2 (0.6) * |
Serum MMI LLOQ = 0.38 ng/ml; Gland MMI LLOQ = 25 ng/g and thyroid gland LLOQ = 0.1 ng/ml
**
indicates significantly different from control group where p<0.05
1
ppm = parts per million
2
MMI = methimazole; (n=8/dose/group)
‡
MIT, 3-monoiodotyrosine, DIT, 3,5-diiodotyrosine, rT3, 3,3’,5’-triiodothyronine, T3, 3,3’,5-triiodothyronine, T4, thyroxine.