Ahmet Gökhan ÖZGEN, Oya BAYINDIR, Füsun HAMULU, Candeğer YILMAZ, Metin ÇETİN, Dilek ÖZMEN

Effects of gliclazide and insulin therapy on thromboxane B2 and 6-keta-PGF1alpha levels in type II diabetic patients

Diabetic patients show hemobiolo-gical abnormalities such as increased platelet adhesiveness, platelet hyperaggregability, decreased platelet half life, hemorheological abnormalities and altered fibrinolysis, perhaps contributing to a procoagulative state. Gliclazide, a novel sulfonylurea in routine clinical use, was thought to have effects on prostanoid release and platelet function. We studied thromboxane A metabolite; serum thomboxane B2 (TXB ] and the prostacyclin metabolite, 6-keto-PGF1 to assess the efficacy of gliclazide on these parameters. Two groups of age and sex matched type Il diabetics were examined in the study. There were 16 subjects in each group (F: M= 10/6). The study period was 12 weeks. Gliclazide was given to the first group and insulin to the second. Following parameters were evaluated to see the effect of good control. HbAIc, cholesterol, triglycéride, HDL cholesterol, LDL cholesterol, serum TXB2,6-keto-PGF] levels were measured before and after 3 months of therapy. There was no significant change in TXB2 (2.24±0.2 to 2.08±0.4 nmol/L) and 6-keto-PGF] (2.53±0.2 to 2.15±0.1 nmol/L,) levels in patients treated with insulin despite the amelioration in the HbAIc levels. Therapy ' with gliclazide was followed by a significant decrease in both serum TXB levels (4.18±0.7 to 2.72±0.4, p=0.039] and 6-keto-PGF (2.97±0.3 to 2.03±0.1, p=0.0047)KTXB /6-keto-PGF] ratio did not change both after insulin (1.09±O.S to 1.06±0.8)and gliclazide (1.31±0.9 to 1.32±0.4) treatment. According to the datas in our study, giiclazide therapy decreased TXB2 levels as well as 6-keto-PGF1a levels so that ratio of TXB.,/6-keto-PGF, did not change, which would 1a 3 mean that gliclazide has neutral effect on diabetic microvascular complications.

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