In the article cluster distribution of liver hepatocytes and their morphological changes in the dynamics and course of streptozotocin-induced diabetes were studied. The liver is a detoxifying organ; the disorders of its structure may cause a change in metabolism of the whole body. Nowadays, many studies are devoted to investigating the structure of hepatocytes of rats’ liver in experimental diabetes. But most of them do not pay attention to the study of their heterogeneity in different areas of hepatic lobules making conclusions based on the average morphometric parameters of the whole lobule. The study was conducted on 12-month Wistar male rats. The animals were divided into 2 groups: control group (5 animals) and experimental group (20 animals). Diabetes was modeled to the experimental animals. It was performed by a single intraperitoneal streptozotocin administration manufactured by “Sigma” (USA) in a dose of 6 mg/100 grams dissolved in 0.1 M citrate buffer (pH 4.5). The equivalent dose of 0.1M citrate buffer (pH 4.5) was administered to the control group. The animals were decapitated under anesthesia with thiopental. The blood and liver were taken for the examination during the 14th, the 28th, the 42nd and the 56th days of the experiment. The histological methods (staining: hematoxylin-eosin, the Shabadash method, Sudan III), electron microscopic and statistical (STATISTICA (StatSoft, Inc. (2011), STATISTICA (data analysis software system), version 10. www.statsoft.com) were used for study. Using morphometric parameters of hepatocytes by cluster analysis in the hepatic lobules three clusters of cells were defined (C1, C2, C3). They differ in their size, area of nucleus and nuclear-cytoplasmic index. It was established that in early stages of diabetes (14th day) the areas of hepatocytes and their nuclei were significantly reduced in all clusters except the second one, the cells which are mainly located around the central vein. During the 28th day the morphometric changes were observed in all clusters, connected with glycogenolysis, glycogenesis disorders and protein synthesis function of hepatocytes. These parameters had histological and ultrastructural confirmation. In the long term course of streptozotocin-induced diabetes (the 42nd and the 56th days) the area of hepatocytes and their nuclei increased. These morphometric changes were associated with different pathological processes. First, due to the development of diabetic angiopathy in hepatocytes hydropic degeneration was developed. It was the most evident: in C3 – large granular degeneration that developed into a ballooning one; in C1 small- and medium drop hydropic degeneration was also seen. Secondly, lipid accumulation in the cytoplasm, leading to fatty degeneration was observed in hepatocytes. Herein, the inclusion of glycogen in hepatocytes was absent. Thus, in the early stages of development (the 14th- the 28th days) streptozotocin-induced diabetes a statistically significant decrease in the area of hepatocytes of all clusters by glycogenolysis and metabolism disorder in them take place. In the later stages of the streptozotocin-induced diabetes course (the 42nd, the 56th days) in the liver diabetic hepatopathy is observed. It is characterized by a statistically significant growth of hepatocyte’s area of all clusters by developing hydropic and fatty degeneration. It should also be noted that different clusters of hepatocytes in the long term, of streptozotocin-induced diabetes course the following polymorphic changes were observed: hydropic, ballooning and fatty degeneration, colliquation necrosis and apoptosis, developed in severe diabetic microangiopathy.
morphological changes, hepatocyte, cluster analysis, streptozotocin-induced diabetes
«Bulletin of problems biology and medicine» Issue 2 part 1 (128), 2016 year, 342-348 pages, index UDK 616-092.9+591.436+616.379-008.64
