Figure 2c: Chromatogram showing endogenous level of melatonin in T effector lymphocyte (Teff) when Teff Lymphocytes (Teffector) were cultured with Dopamine (DA) Trace amount of melatonin concentration was noted with treatment of D.A. Sample Flow rate-1ml/ min No of Cell=1 × 106 (N=5 separate experiments).