Effects of S-adenosyl-L-methionine on platelet thromboxane and vascular prostacyclin

We therefore designed the present study to evaluate the effect of S-adenosyl-L-methionine (SAMe) on the synthesis of platelet thromboxane and vascular prostacyclin. The experimental materials were human blood and aortic rings from untreated Wistar rats; and platelets and aortic rings from Wistar rats treated for 7 days with SAMe at 5 or 10 mg/kg/day s.c. The administration of 10 mg/Kg/day of SAMe to rats significantly increased vascular production of 6-keto-PGF_1α. In vitro vascular production of 6-keto-PGF_1α increased in a concentration-dependent manner when SAMe was incubated in the range of 10⁻⁷ to 10⁻⁴ M. The greatest increase was 167 ± 15%, obtained in samples incubated with 5 × 10⁻⁵M SAMe. In aortic rings, lipid peroxidase production was inhibited in a concentration-dependent manner in the SAMe range of 10⁻⁷ to 10⁻⁵ M. Maximum inhibition (75.3 ± 6.2%) was obtained with SAMe at 1.5 × 10⁻⁵M. Vascular 6-keto-PGF_1α production showed a significant inverse linear correlation with vascular lipid peroxide production (Y = −0.04 × + 18.1, r = 0.7309, P < 0.0001).