Table 3.
Representative xenobiotic hydrolase activities in skin of various mammalian species
| Substrate (for) | Human | Rat | Mouse | Pig |
|---|---|---|---|---|
| Phenyl acetate (E) | 1,130 ± 25c (micr) | |||
| 3,440 ± 1400d (cytos) | ||||
| Naphthyl acetate (E) | 90 ± 6a (micr) | 1,500 ± 70a (micr) | 28 ± 3a (micr) | |
| 47 ± 3a (cytos) | 280 ± 1a (cytos) | 85 ± 9a (cytos) | ||
| Para-nitrophenyl acetate (E) | 91 ± 4a (micr) | 2,100 ± 100a (micr) | 46 ± 6a (minipig micr) | |
| 45–86a (cytos) | 380 ± 20a (cytos) | 155 ± 18a (minipig cytos) | ||
| 188 ± 30a (S9) | ||||
| Para-nitrophenyl butyrate (E) | 460 ± 127a (S9) | |||
| 4-Methylumbelliferone acetate (E) | 0.5a (S9) | |||
| Carbaryl (E) | 0.2 ± 0.03c (micr) | + | ||
| 0.5 ± 0.12d (cytos) | ||||
| Fluroxypyr methyl ester (E) | 1400b (homogenate) | |||
| Fluroxypyr methylheptyl ester (E) | 490b (homogenate) | |||
| Fluazifo p-butyl (E) | 20 ± 1.5c (micr) | |||
| 400 ± 60d (cytos) | ||||
| Methylparaben (E) | ~400a (micr) | ~390a (minipig micr) | ||
| ~550a (cytos) | ~570a (minipig cytos) | |||
| Ethylparaben (E) | ~420a (micr) | ~400a (minipig micr) | ||
| ~520a (cytos) | ~440a (minipig cytos) | |||
| Propylparaben (E) | ~100a (micr) | ~150a (minipig micr) | ||
| ~210a (cytos) | ~380a (minipg cytos) | |||
| Butylparaben (E) | ~80a (micr) | ~100a (minipig micr) | ||
| ~150a (cytos) | ~140a (minipig cytos) | |||
| Benzylparaben (E) | ~50a (micr) | ~30a (minipig micr) | ||
| ~180a (cytos) | ~170a (minipig cytos) | |||
| Ethyl nicotinate (E) | 27.3 ± 11.7a (S9) | 6.46 ± 1.14a (S9) | ||
| Prodrug esters (E) | + (Many) | + (Many) | + (Many) | + (Alkylazacycloalkan-2-one prodrug esters) |
| Phenanthrene 9,10-oxide (mEH) | 2.53a (micr) | 0.808a (micr) | 1.58a (micr) | |
| Benz[a]anthracene 5,6-oxide (mEH) | 0.526a (micr) | 0.11a (micr) | 0.129a (micr) | |
| Benzo[a]pyrene 4,5-oxide (mEH) | 0.175–0.447a (micr) | 0.12–0.16a (micr) | 0.111–0.172a (micr) | |
| 7-Methylbenz[a]anthracene 5,6-oxide (mEH) | 0.384a (micr) | 0.119a (micr) | 0.159a (micr) | |
| 3-Methylcholanthrene 11,12-oxide (mEH) | 0.059a (micr) | 0.004a (micr) | 0.023a (micr) | |
| Dibenz[a,h]anthracene 5,6-oxide (mEH) | 0.021a (micr) | 0.0015a (micr) | 0.003.5a (micr) | |
| Styrene 7,8-oxide | 0.15 ± 0.03a (micr) | |||
| Cis-stilbene oxide | 0.11–0.0160a (micr) | |||
| Trans-stilbene oxide (sEH) | 0.027–0.043a (cytos) |
More examples and references in the text; only constitutive activities
S9 9,000g supernatant fraction, cytos cytosol, E esterase, FPMH fluroxypyr methylheptyl ester, mEH microsomal epoxide hydrolase (EH1; EPH1), micr microsomes, sEH soluble epoxide hydrolase (EH2; EPH2)
anmol product/min/mg protein
bµmol/min/g of tissue
cnmol/min/g microsomal fraction
dnmol/min/g cytosolic fraction