Abstract: Objective To investigate the effects of calcip otriene,tretinoin and triptolide on mRNA expression of vascular endothelial growth factor(VEGF)in primary cultured keratinocytes a nd COLO16 cell line.Methods VEGF mRNA levels were determined by reverse transcriptase polymerase ch ain reaction(RT-PCR).Results Calcipotriene inhibited the mRNA expression of VEGF in a dose-dependent manner in keratinocytes after4hour and 24hour treatment.The 50%i nhibitory concentation values(IC 50)of calcipotriene were 1.19×10^-4μg/mL(KC 4h),1.51×10^-4μg/mL(KC 24h)and 3.16×10^-5μg/mL(COLO1624h)respectively.Tretinoin in-hibited the mRNA expression of VEGF in keratinocytes after 4hours,and had no inhibition in keratinocytes after 24hours and in COLO16 cells after 4hour s and 24hours.Triptolide had no inhibition.Conclusions The antipsoriatic effect of calcipotriene and tretinoin may be partly explained by their in hibition on VEGF production at transcription level.

Key words: Endothelial growth factors, Calcipotriene, Tretinoin, Triptolide