TABLE 2

LC/MS-MS determination of nicotine glucuronidation by UGT1A3, UGT1A4, and UGT1A9

Nicotine glucuronide was detected by LC/MS-MS after a 2-h incubation of enzyme preparations with 5 mM nicotine and 2 mM UDPGA. Quantification was by the addition of known quantities of nicotine glucuronide. Details are described under Materials and Methods.


UGT

Rate

Relative Expressiona

Relative Rateb
pmol/mg
1A3 Supersomes 52 13 4
1A4 Supersomes 1550 13 119
1A9 Supersomes 20 13 2
V79 1A9
35
1
35
  • a Relative protein expression was determined by Western blot analysis with an antibody directed against UGT1A enzymes as described under Materials and Methods.

  • b Rates are adjusted for the relative levels of UGT1A protein expressed per milligram of total protein.