This study elucidates the relationship among hypercoagulability, microviscosity of platelet and lymphocyte, and lipids in serum and platelet of hyperlipidemic patients, especially of diabetes mellitus. The effect of pantethine on these parameters is also studied.
The microviscosity was measured with the microviscosimeter (The Elscint Co. Ltd. Israel) using DPH labeling at 25°C for 60min. Aggregation of the platelet induced by ADP was obtained with the Sienco dual sample aggregation meter (The Sienco, Inc. USA). Pantethine (The Daiichi-Seiyaku KK, Japan) was injected intravenously 10mg/kg or 100mg/kg and the venous blood added heparin or sodium citrate was taken before and 15min after injection. In vitro effect of pantethine on the microviscosity of platelets and lymphocytes was also studied successively at 15, 60, and 180min after incubation.
The microviscosity of healthy lymphocytes was 2.88±0.140 (M±SD) at 25°C, and 2.86±0.275 in diabetic lymphocytes with greater variation than healthy lymphocytes. Serum phospholipid was well correlated negatively with lymphocyte microviscosity (r=-0.34, p<0.05), but not with cholesterol, triglyceride and free fatty acid. Higher microviscosity was observed in platelets than lymphocytes, and in healthy platelets than diabetic platelets. Pretreatment (extra vivo) of healthy and diabetic platelets with pantethine at 10mg/ml concentration increased their microviscosities. Intravenously injected pantethine (10mg/kg) decreased ADP aggregation in 33.3% of cases, and increased in 26.7% at 15min after injection. Phospholipid in cases of decreased ADP aggregation reduced after injection of pantethine in both serum and platelets, in spite of few changes in cholesterol of serum and platelets, and in triglyceride and free fatty acid of serum. Fifteen min after injection of 100mg/kg of pantethine, the microviscosity increased slightly in platelets and lymphocytes in 2 diabetic patients out of three.
Incubation of platelets and lymphocytes in vitro with 1, 10, 100mg/ml of pantethine, the microviscosity increased at 60min in platelet and at 15min in lymphocyte.
As conclusion, the microviscosity of platelets was higher than lymphocytes. Healthy platelets had higher poise than diabetic platelets. Pantethine increased microviscosity of platelets and lymphocytes in vivo as well as in vitro. These changes of microviscosities were correlated with phospholipid level in serum and platelet negatively and molar ratio of cholesterol/phospholipid, positively.
