Ten cigaret smokers took seven puffs from a 10 mg 'tar' yield test cigaret and a fixed volume of air (0, 75, 250, 500 or 1000 mL) to give controlled depth of inhalation. Subjects exhaled normally after a 2-second breath hold with exhalation passing through a filter pad for the collection of non-retained nicotine and solanesol. Blood samples were taken before and at intervals during and after smoking. A second series of experiments was conducted with a fixed inhalation volume (500 mL) and three breath hold durations (0, 2, and 10 seconds). Solanesol retention increased from 34.2% at zero inhalation volume to 71.9% at 1000 mL inhalation volume ( for 2-second breath hold) and from 51.8% at zero breath hold to 87.6% at 10-second breath hold (500 mL inhalation).

Normal human hepatic cell L02 was cultured in DMEM media containig 10% (v/v) fetal bovine serum, 100 U/mL penicillin and 100 micro-g/mL streptomycin at 37 deg-C ina 5% CO2 atmosphere. Cells were cultured with different concentrations of solanesol (0 - 80 micro-M) for 12 hours. Relative HO-1 and Hsp70 mRNA expressions were determined using real-time polymer chain reaction and calculated by subtracting the Ct value for GAPDH from the Ct value for HO-1 or Hsp70. Solanesol increased mRNA and protein levels of HO-1 and Hsp70 in a dose-dependent manner.