Effect of Endothelin on Expression of Nitric Oxide Synthetase of Vascular Smooth Muscle Cell Gene

With reverse transcripti0n-polymerase chain reaction （RT-PCR）,it has been found that NOS mRN;\ is widely distributed in cells of car＜liovascular system such as t’ardiomyocytes, endothelia1 cels, vascular smooth musclc cel1s （VSMC ）. When ET （1O-’ mol/L ） was added to cu1tured VSMC, it significant1y increased the NOS mRNA leve1 in VSMC （+ 34. 8% ）. By measuring the enzyme activity of NOS in cultured VSMC,it was f0und that when VSMC was treated with ET （2 X 10wv mol/L） l NOS activati0n was significantly increased （79% ） compared to the contr0l. These data show that the increased expression of NOS gene inVSMC induced by ET may be an important regulat0ry factor for hypertension.