Table 5.
Chemical and biological parameters of the investigated inhibitors of AChE administered prophylactically before exposure to OPCs.
| Reversible AChE Inhibitor | Molecular Weight | IC50 (μM) | LD01 (μmol/rat) | LD50 (μmol/rat) | Injected Dose (μmol/rat) |
|---|---|---|---|---|---|
| Physostigmine | 275.35 | 0.012 | 0.9 | 3.0 | 0.25 |
| Pyridostigmine | 261.12 | 0.33 | 3.7 | 7.2 | 1 |
| Tacrine | 250.00 | 0.2 | 16 | 21.5 | 4.00 |
| Ranitidine | 350.86 | 2.5 | 46 | 59 | 12.00 |
| K027 | 446.16 | 414 | 250 | 350 | 60.00 |
Column 2 lists their molecular weights, column 3 their concentration necessary to inhibit 50% of human red blood cell AChE activity (IC50) (Lorke et al., 2011), column 4, their LD50 values for intraperitoneal (i.p.) application in rats, column 5 their LD01 values, and column 6 the doses injected i.p. for pretreatment 30 min before OPC exposure to assess their efficacy to protect from OPC-induced mortality. The injected doses are approximately one fourth the LD01.