Potencies for clinically used progestins, antiprogestins, endogenous steroid hormones and androgens to elicit calcium influx in human sperm
| # | Steroid | Steroid Alone | +30 µM Mibefradil | ||||||
|---|---|---|---|---|---|---|---|---|---|
| pEC50 | Emax, % | n | pEC50 | Emax, % | n | ||||
| Progestins and Anti-progestins | 4 | MPA | <5 | 17 | 3 | — | <10 | 3 | |
| 5 | LNG | <5 | 15 | 6 | — | <10 | 2 | ||
| 31 | drospirenone | 6.28 ± 0.22 | 115 | 5 | — | <10 | 4 | ||
| 32 | ulipristal | 5.45 ± 0.22 | 106 | 3 | <5 | 12 | 5 | ||
| 33 | mifepristone (RU-486) | 5.33 ± 0.30 | 109 | 4 | — | <10 | 5 | ||
| 34 | ulipristal acetate | <5 | 27 | 3 | — | <10 | 3 | ||
| 35 | segesterone acetate | <5 | 57 | 4 | — | <10 | 4 | ||
| Endogenous | 6 | ALDO | — | <10 | 3 | — | <10 | 1 | |
| 36 | testosterone | 6.66 ± 0.22 | 114 | 3 | <5 | 17 | 4 | ||
| 37 | 17β-estradiol | 6.53 ± 0.25 | 94 | 3 | <5 | 37 | 1 | ||
| Androgens | 38 | 11β-methyl-19-nortestosterone | 6.37 ± 0.32 | 85 | 6 | 6.27 ± 0.25 | 15 | 3 | |
| 39 | 7α-methyl-19-nortestosterone | 6.25 ± 0.37 | 86 | 7 | 6.29 | 26 | 2 | ||
| 40 | 7α,11β-dimethylandrolone | 6.06 ± 0.49 | 80 | 9 | <5 | 11 | 3 | ||
| 41 | 7β,11β-dimethylandrolone | 5.41 ± 0.24 | 42 | 5 | <5 | 26 | 3 | ||
The potency (EC50 values, mean ±SD) and maximum response (Emax) produced by each compound was determined in the absence and presence of 30 µM mibefradil. Emax is expressed as a percent of the response produced by a saturating concentration of PROG (3 µM). The number of independent experiments indicated by n. Fitted parameters were not calculated for compounds producing Emax < 10%.