Table 4

Correlation coefficients (r) for comparing the formation of various E₂ metabolites with the activities of CYP1A2, 2B6, 3A4, or 3A4/5 by measuring the metabolism of probe substrates in 33 human liver microsomes (21 male and 12 female)

E₂ Metabolite Formed	Total CYP Content		CYP1A2 (Caffeine N 3-Demethylation)		CYP2B6 ( S -Mephenytoin N -Demethylation)		CYP3A4 (Dextromethorphan N -Demethylation)		CYP3A4/5 (Testosterone 6β-Hydroxylation)
E₂ Metabolite Formed	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total
y -OH-E₂	0.70^4-165	0.90^4-165	0.79^4-165	0.43	0.54	0.40^4-150	0.66^4-160	0.94^4-165	0.80^4-165	0.80^4-165	0.90^4-165	0.87^4-165	0.91^4-165	0.94^4-165	0.94^4-165
16α-OH-E₂	0.59^4-160	0.81^4-160	0.72^4-165	0.36	0.41	0.35^4-150	0.71^4-165	0.87^4-165	0.80^4-165	0.72^4-165	0.81^4-160	0.78^4-165	0.74^4-165	0.88^4-165	0.82^4-165
y -OH-E₁	0.72^4-165	0.90^4-165	0.82^4-165	0.35	0.46	0.34	0.54^4-150	0.86^4-165	0.72^4-165	0.59^4-160	0.78^4-160	0.73^4-165	0.80^4-165	0.96^4-165	0.92^4-165
6β-OH-E₂	0.65^4-160	0.81^4-160	0.74^4-165	0.40	0.56	0.43^4-150	0.38	0.86^4-165	0.67^4-165	0.45^4-150	0.82^4-160	0.71^4-165	0.62^4-160	0.84^4-165	0.78^4-165
6β-OH-E₁ ⁺ 6-keto-E₂ ⁺ 16α-OH-E₁ ⁺16β-OH-E₁ ⁺16-keto-E₂	0.56^4-150	0.86^4-165	0.73^4-165	0.49^4-150	0.33	0.36^4-150	0.71^4-165	0.73^4-160	0.72^4-165	0.70^4-165	0.73^4-160	0.72^4-165	0.55^4-150	0.92^4-165	0.77^4-165
16β-OH-E₂	0.62^4-160	0.82^4-160	0.71^4-165	0.45^4-150	0.47	0.36^4-150	0.70^4-165	0.87^4-165	0.76^4-165	0.76^4-165	0.87^4-165	0.84^4-165	0.70^4-165	0.87^4-165	0.84^4-165
4-OH-E₂	0.75^4-165	0.87^4-165	0.82^4-165	0.44	0.51	0.42^4-150	0.65^4-160	0.90^4-165	0.79^4-165	0.75^4-165	0.90^4-165	0.85^4-165	0.86^4-165	0.92^4-165	0.90^4-165
2-OH-E₂	0.72^4-165	0.92^4-165	0.83^4-165	0.44	0.63^4-150	0.52^4-160	0.65^4-160	0.95^4-165	0.82^4-165	0.75^4-165	0.94^4-165	0.86^4-165	0.86^4-165	0.93^4-165	0.88^4-165
2-OH-E₁	0.65^4-160	0.87^4-165	0.76^4-165	0.32	0.41	0.34	0.39	0.75^4-160	0.58^4-165	0.28	0.64^4-150	0.48^4-160	0.67^4-160	0.91^4-165	0.77^4-165
4-OH-E₁	0.56^4-150	0.92^4-165	0.77^4-165	0.25	0.35	0.27	0.37	0.67^4-150	0.55^4-160	0.34	0.62^4-150	0.54^4-160	0.66^4-160	0.92^4-165	0.83^4-165
E₁	0.40	0.48	0.43^4-150	0.05	−0.07	−0.01	0.12	0.15	0.13	−0.09	0.01	−0.04	0.36	0.49	0.38^4-150
X	0.38	0.61^4-150	0.49^4-160	0.37	0.34	0.22	0.50^4-150	0.72^4-165	0.59^4-160	0.34	0.57	0.51^4-160	0.45^4-150	0.66^4-150	0.63^4-165
Total E₂metabolized	0.71^4-165	0.86^4-165	0.79^4-165	0.41	0.39	0.32	0.59^4-165	0.79^4-165	0.70^4-165	0.45^4-150	0.67^4-150	0.61^4-165	0.77^4-165	0.90^4-165	0.86^4-165

The microsomal formation of various estrogen metabolites was as described in the legend to Table 3. The CYP1A2, 2B6, 3A4, or 3A4/5 activites in human liver microsomes were determined by the supplier by measuring the activities for caffeine N 3-demethylation, S -mephenytoin N -demethylation, dextromethorphan N -demethylation, or testosterone 6β-hydroxylation, respectively, according to published methods (Pearce et al., 1996).

↵4-150 P < 0.05;
↵4-160 P < 0.01;
↵4-165 P < 0.001.