TABLE 1.
ED50 values of androsterone (5α,3α-A), etiocholanolone (5β,3α-A) and epiandrosterone (5α,3β-A) for protection in the 6 Hz electrical stimulation, pentylenetetrazol (PTZ), pilocarpine, 4-aminopyridine (4-AP) and maximal electroshock (MES) seizure models in mice
| Androsterone epimer | Seizure model | ED50 (mg/kg)a | PIb |
|---|---|---|---|
| 5α,3α-A | 6 Hz | 29.1(16.2–52.1) | 5.23 |
| 5β,3α-A | 6 Hz | 76.9 (53.7–109.9) | 1.98 |
| 5α,3β-A | 6 Hz | > 300 | N.D. |
| 5α,3α-A | PTZ | 43.5 (31.6–60.0) | 3.50 |
| 5β,3α-A | PTZ | 138.7 (110.5–169.8) | 1.53 |
| 5α,3β-A | PTZ | > 300 | N.D.c |
| 5α,3α-A | Pilocarpine | 105.4 (47.7–232.7) | 1.44 |
| 5α,3α-A | 4-AP | 215.3 (173.8–266.6) | 0.70 |
| 5α,3α-A | MES | 223.7 (182.5–274.1) | 0.68 |
a
ED50 values (with 95% confidence intervals) represent the dose in mg/kg that is estimated to protect 50% of animals.
b
PI (protective index) is the ratio between TD50 (the dose estimated to produce motor impairment in 50% of animals) and the ED50. The TD50 value for 5α,3α-A was 152.3 (133.9–173.1) mg/kg, while the TD50 for its 5β-epimer was 212.3 (150.8–298.7). 5α,3β-A did not cause motor impairment at doses as high as 300 mg/kg.
c
N.D., not possible to determine.