Table 1.

Probe Substrates and Respective Metabolites Used to Characterize the Activities of Major CYP and UGT Enzymes in Northern Gulf of Mexico Fish Microsomes

enzyme	probe substrate	metabolite
CYP (phase I)
CYP1A2	phenacetin (PCN)	acetaminophen (ACP)
CYP2C9	tolbutamide (TB)	4-hydroxytolbutamide (4-OH-TB)
CYP2D6	dextromethorphan (DEX)	dextrophan (DOR)
CYP2E1	chlorzoxazone (CH)	6-hydroxychlorzoxazone (6-OH-CH)
CYP3A4	midazolam (MDZ)	4-hydroxymidazolam (4-OH-MDZ)
UGT (phase II)
UGT1A1	β-estradiol (E2)	β-estradiol 17-β-d-glucuronide (E2-GlcA)
UGT1A4	trifluoperazine dihydrochloride (TFP)	trifluoperazine N-β-d-glucuronide (TFP-GlcA)
UGT1A6	N-acetylserotonin (NAS)	N-acetyl serotonin β-d-glucuronide (NAS-GlcA)
UGT1A9	mycophenolic acid (MA)	mycophenolic acid-β-d-glucuronide (MA-GlcA)
UGT2B7	naloxone (NLX)	naloxone-3β-d-glucuronide (NLX-GlcA)