Changes in glucose, cholesterol and serum lipid fraction levels in experimental diabetes

The objective of this research was to trace the changes in serum glucose, cholesterol and lipid fractions during progression of diabetes in rabbits. 89 male rabbits, New Zealand breed were used in the experiment. Diabetes mellitus was induced by a single injection of alloxan. On day 7 the glucose level in the whole blood was measured by a glucometer to confirm the presence of diabetes. From this day the time of disease was counted. The rabbits were divided into the following groups: Group 1--controls (n = 18), Group 2-21 days diabetes mellitus (n = 18), Group 3-42 days diabetes mellitus (n = 17), group 4-90 days diabetes mellitus (n = 19), group 5-180 days diabetes mellitus (n = 17). After above-mentioned periods blood samples were taken and the rabbits were killed by decapitation. The final level of glucose in the sera was determined spectrophotometrically by enzymatic method. The method of cholesterol measurement was based on oxidation of free cholesterol to cholesterol releasing hydrogen peroxide. Measurement of lipid fractions was based on indirect methods consisting in precipitation of specific lipoprotein fractions. Control rabbits revealed highly significant (p < 0.01) or significant (p < 0.05) correlation between initial and final cholesterol and glucose levels. It was not observed in diabetic rabbits. Highly significant correlation (p < 0.01) was found between LDL and total cholesterol concentration in 21 and 42 day of diabetes. Similar correlation was observed between HDL and total cholesterol concentration on 90th day of the course of disease. We concluded that significant disorders of lipid metabolism occur in the course of alloxan-induced diabetes in rabbits, manifested by total cholesterol level increase and changes in proportions and levels of serum lipid fractions.