Table 1

CE activity and CPT-11 conversion by control and Es1e mouse plasma and tissue extracts

CE activity was calculated from spectrophotometric assays using o-nitrophenyl acetate as a substrate and SN-38 conversion by HPLC.

MouseTissueCE activity (μmol/min/mg)SN-38 (pmol/h/mg)SN-38 (% of control)
ControlPlasmaa2983 ± 13311207
Es1 e Plasmaa792.5 ± 83.9144.21
Es1 e Plasmaa + BNPPb327.6 ± 30.219.6
Es1 e Plasmaa + tacrineb340.4 ± 17.377.5
ControlBrain40.4 ± 7.00.4
Es1 e Brain35.7 ± 4.40.125
ControlHeart29.6 ± 3.72.8
Es1 e Heart41.0 ± 6.30.27
ControlKidney163.5 ± 11.77.5
Es1 e Kidney145.3 ± 29.73.141
ControlLiver293.4 ± 50.045.5
Es1 e Liver303.1 ± 10.334.876
ControlLung61.2 ± 1.64.1
Es1 e Lung80.1 ± 5.60.820
ControlSmall intestine208.3 ± 13.910.0
Es1 e Small intestine554.3 ± 173.114.6146
ControlSpleen13.5 ± 3.61.3
Es1 e Spleen13.3 ± 1.00.18
  • a Values for plasma are expressed as μmol/min/ml for CE activity and pmol/h/ml for SN-38 conversion.

  • b Inhibitor concentrations were 1 mm.