1987 Volume 9 Issue 4 Pages 354-370
For the purpose to elucidate the relationship between cerebrovascular disease (CVD) and disorders of lipid metabolism, we analysed serum lipids, lipoproteins and apoproteins in CVD with a particular emphasis on the chemical composition and the size of LDL. CVD were classified according to the findings on the lesions by brain computed tomography as cerebral bleeding, perforating artery infarction and cortical artery infarction, the results being compared between CVD and the control, and among the CVD subgroups.
The subjects employed in this study were 63, only male patients with CVD, and 38 normal healthy control. The patients were all on rehabilitation program for 2 to 12 months after stroke episode, among whom 27 had cerebral infarction within cortical artery region, 21 infarction within perforating artery region, and 15 cerebral hemorrhage.
They were examined on fasting blood plasma for total cholesterol (TC), triglycerides (TG) by enzymatic methods, lipoproteins of VLDL, LDL and HDL by ultracentrifugation with a use of Lp-42 Ti rotor, and apoproteins of A-I, A-II, B, C-II, C-III and E by single radial immunodiffusion. LDL isolated were stained negatively and viewed under transmission electron microscopy, and their diameters measured on enlarged photographs. When we compared the total CVD with the control, TG and VLDL-c were significantly higher in the CVD than in the control, while HDL-c, apo-A-I and A-II were significantly lower in the CVD than in the control. Apo C-II and E tended to be higher in the CVD but not significant, apo C-III had no difference.
Cholesterol ratio (TC-HDL-c/HDL-c) and LDL-c/HDL-c ratio were significantly higher in CVD, while the ratios of A-I/B and A-II/B were significantly lower in CVD when compared with those of the control.
When we looked into the CVD subgroups, TC, LDL-c, apoB and LDL-apo B were higher in the infarction of cortical artery region than in the control, while they were lower in the cerebral bleeding than in the control, among which statistically significant were the elevation of LDL-c, apoB in cortical infarction group, and the low levels of TC and LDL-apoB in cerebral bleeding group.
Since LDL differed significantly in cholesterol and apoB contents among CVD subgroups, we examined the size of LDL in each group, and found that LDL was significantly larger in the descending order of cortical artery infarction, perforating artery infarction, control, and cerebral bleeding.
We computed by multivarite analysis the contributing factors (s) to determine LDL-size, setting LDL-c as criteion variable and lipoprotein and apoprotein parameters as explenary variables. We gained a multiple regression equation, whose partial regression coefficients were greater in the order of VLDL-c, HDL-c and apo E, indicating that these three factors were the major determinants of LDL-size.
This is in good concrdance with hypertriglyceridemias observed in common with CVD subgroups, and with the fact that serum triglyceride level or triglyceride content in VLDL affects via VLDL-HDL cycle the size of LDL and the level of HDL-c, Yet, the relation between LDL-size and exact mechanism for pathogenesis of arterisclerosis in cerebral arteries remains to be studied.
