Table 4.
Antidotal efficacy of oxime TAB2OH and human BChE in OP exposed mice. Protective index is the ratio of LD50 for OP exposed animals with pretreatment/therapy and animals exposed to OP only. In parentheses 95% confidence limits of Protective Index and MDP (the highest multiple of the OP LD50, which was fully counteracted by the antidotal treatment) are also given.
| Pretreatment (i.v.) | Therapy (i.m.) | VXa | Paraoxonb | |||
|---|---|---|---|---|---|---|
| 15 min | 30 min | 1 min after OP | Protective Index (95% conf. limits) |
MDP | Protective Index (95% conf. limits) |
MDP |
| 25 mg/kg TAB2OH | 1.3 (0.7–2.1) |
1.3 | ||||
| 10 mg/kg TAB2OH with atropine |
2.7 (2.5–3.0) |
2.5 | ||||
| 25 mg/kg TAB2OH with atropine |
5.0 (2.2–11.7) |
3.2 | 10.0 (7.5–13.3) |
6.3 | ||
| 0.5 mg/kg hBChE | 1.0 (0.9–1.1) |
0.79 | ||||
| 1 mg/kg hBChE | 1.1 (0.8–1.4) |
nd | <1.0 (nd) |
nd | ||
| 0.5 mg/kg hBChE | 10 mg/kg TAB2OH with atropine |
3.4 (2.7–4.4) |
3.4 | |||
| 1 mg/kg hBChE in atropine |
2.5 (1.3–4.8) |
1.3 | ||||
| 1 mg/kg hBChE | 25 mg/kg TAB2OH with atropine |
5.0 (3.3–7.7) |
3.2 | 14.1 (12.0–16.7) |
10 | |
| 1 mg/kg hBChE with 25 mg/kgTAB2OH |
<1 (nd) |
nd | <1 (nd) |
nd | ||
| 1 mg/kg hBChE with 25 mg/kg TAB2OH |
<1 (nd) |
nd | ||||
| 1 mg/kg hBChE with 25 mg/kg TAB2OH |
25 mg/kg TAB2OH with atropine |
5.0 (3.3–7.7) |
3.2 | 16 (13.5–18.7) |
13 | |
| 1 mg/kg hBChE + 25 mg/kg TAB2OH with atropine |
13 (8.2–19.1) |
7.9 | ||||
a
s.c. LD50 of VX was 28 µg/kg.
b
s.c. LD50 of Paraoxon was 740 µg/kg.