Activity of ginsenoside Rh₂ on the growth of mice splenic lymphocytes investigated by microcalorimetry and factor analysis

The power-time curves of mice splenic lymphocytes growth at 37 A degrees C affected by ginsenoside Rh-2 were determined by microcalorimetry using a 3114/3236 TAM air bioactivity monitor with ampoule mode. Then, the minimal inhibitory concentration (MIC) of Rh-2 on splenic lymphocytes growth was determined by serial dilution method. From factor analysis (FA) on six quantitative thermokinetic parameters from the power-time curves, the activity of Rh-2 on splenic lymphocytes could be quickly evaluated by analyzing the changes in the two main parameters: growth rate constant k, and maximum heat-output power, P (m). The results showed that Rh-2 had strong inhibitory activity on splenic lymphocytes growth, and this inhibitory activity was strengthened with increasing concentration of Rh-2 in the concentration range of 1.0-32.0 mu g mL(-1). This strong inhibitory also could be confirmed from the MIC of 50.0 mu g mL(-1) of Rh-2 on splenic lymphocytes growth in RPMI-1640 culture medium. This study illustrated that microcalorimetry could not only offer a useful method for evaluating the activity of drugs, but also serve as a quantitative, sensitive, and simple analytic tool for the evaluation of drugs on cell growth.