TABLE 5.
Cholesterol 7α-hydroxylation activity in human liver (HL) microsomes
| Human liver microsomes, sample number | Cholesterol | P450 7A1a | 7α-Hydroxylation activity | 7α-Hydroxylation activity |
|---|---|---|---|---|
| nmol/mg microsomal protein | pmol/mg microsomal protein | pmol/min/mg microsomal protein | nmol/min/nmol P450 7A1 | |
| HL39 | 91 | 0.78 | 1.2 | 1.6 |
| HL97 | 41 | 1.64 | 2.8 | 1.7 |
| HL98 | 66 | 1.84 | 1.5 | 0.8 |
| HL100 | 55 | 1.59 | 2.3 | 1.5 |
| HL103 | 86 | 1.78 | 3.3 | 1.9 |
| HL109 | 47 | 2.54 | 2.7 | 1.1 |
| HL112 | 45 | 1.77 | 1.6 | 0.9 |
| HL132 | 35 | 1.75 | 1.7 | 1.0 |
| HL135 | 57 | 1.75 | 1.2 | 0.7 |
| HL140 | 38 | 2.10 | 6.7 | 3.2 |
| Average | 56 ± 20 | 1.75 ± 0.44 | 2.5 ± 1.6 | 1.4 ± 0.7 |
a Immunoblot analysis, quantified based on the Fe2+-CO versus Fe2+ difference spectrum of purified P450 7A1 using human P450 7A1 antibody (ab79847, Abcam).