It is generally suspected that microhemodynamic changes and hemorheological alterations may play main roles in the pathophysiology of diabetic microangiopathy. Normal subjects, borderline subjects and diabetic subjects were used for this experiment. This study was evaluated from two aspects, first; from the aspect of microhemodynamic change, second; from the aspect of clinical feature. To know the microhemodynamic changes of diabetes mellitus affter 75g-oral glucose tolerance test (75g-OGTT), diabetic subjects were classified into three subgroups; DM-1 group, DM-11 group and DM-111 group. In the increase of blood flow volume, DM-1 group responded to glucose administration more than 200% and DM-11 group responded less than 100%. DM-111 group was placed intermediately between DM-1 group and DM-I1 group. Furthermore, to know the relationship between clinical feature and microangiopathy of diabetes mellitus, diabetic subjects were subdivided into three subgroups; A group, B group and C group. A group was without retinopathy, B group was with simple retinopathy and C group was with proliferative retinopathy. They were examined for microhemodynamic changes of venules on the human bulbar conjunctiva and hemorheologicl alterations in peripheral blood before and after 75-OGTT. Materials and Methods
59 diabetic s ubjects including 23 DM-1,25 DM-11 and 11 DM-111 (23 A,20 B and 16C),11 borderline (borderline group) and 14 normal subjects (normal group) were examine d in this experiment. The venules (average internal diameter of 48 ±2.9 μm) on the bulbar conjunctiva were used for measuring of microhemodynamic changes in internal diameters and flow velocities by using Intra-Vital Video Microscopic System (IVVMS). The Distance Meter Method developed by Tsushima was used to determine blood flow velocities. Blood flow volumes were calculated by multiplying cross sectional area and average flow velocity on the assumption that the vessel cross section was round. Viscosities of whole blood and plasma were measured at 94.5 sec-1 and 0.376 sec-1 by using of Contraves Low Shear-30. In order to know the deformability of erythrocyte, the passage time of 40% red cell suspensions through the micropore filtration membrane (pore size of 5μm) under 10 cm H2O pressure was measured. Factors of hemocoagulation and fibrinolysis were also measured (fibrinogen, antithrombin-111, a2-macroglobulin, plasminogen and a2-plasmin inhibitor).
