Changes in Pancreas Histological Structure in Case of Alloxan Induced Hyperglycemia in Rats according to Age Aspect

The purpose of the study was to examine structural changes of the pancreas after aloxan-induced diabetes in young, mature and old rats. The histological investigation of the rat's pancreas of the intact and experimental groups of all ages has been performed. During the experiment specific changes were detected depending on a particular age group. The most pronounced are changes in the groups of mature and elderly rats. Materials and methods. 36 rats were examined during the experiment. Group of young rats aged 4-5 months (M) consisted of 6 intact (MI) and 6 experimental (ME) rats. A group of mature rats (Z) consisted of 6 intact (ZI) and 6 experimental (ZE) rats aged 7-8 months. A group of elderly rats (S) is represented by 6 intact (SI) and 6 experimental (SE) rats aged 9-10 months. All experimental rats received aloxane at a rate of 150 mg/kg. The animals were withdrawn from the experiment for 30 days. Histological preparations were made according to all rules using standard methods. The preparations were stained with hematoxylin-eosin. Microscopic studies were carried out on an increase in Ch10, Ch40 and Ch60 using a microscope Primo Star (Carl Zeiss, Germany). Results. In comparison with the MI group, the number and area of pancreatic islets in the rat's pancreas of the ME group decreased. There is edema; the vessels were a fool of blood, red blood cells in vessels were not altered. The boundaries between pancreocytes were fuzzy. The capsule was not thickened. The walls of the vessels and ducts had not been changed. Unlike the group ZI, there was a thickening of the capsule, weakly and moderately severe swelling of the stroma, areas of necrosis in micropreparations of rat's pancreas of the ZE group. The islands of Langerhans were in a state of atrophy of varying degrees of severity with signs of multiple sclerosis and hyperplasia. The walls of the vessels were thickened, a cellular reaction in the form of a moderate leukocyte response. There were hemorrhages. Duct walls were thickened. In the study of the histological structure of the glands of animals in the group of SE changes were observed in the direction from the head to the tail. The capsule was not thickened. In the part of the head, the acinuses were enlarged in size; the boundaries between the pancreacytes were fuzzy. In the direction of the tail a pronounced edema was found. The vessels were spasmodic, narrowed, filled with unchanged red blood cells. Blood filling was uneven, closer to the tail part - moderate. The number of Langerhans islands in the area of the head was normal and decreased towards the caudal part of the pancreas, with areas of necrosis and diffuse overgrowth of the connective tissue. Conclusions. After aloxane-induced diabetes, destructive changes were observed in both the exocrine and endocrine parts of the pancreas. Morphological changes in the structure of pancreatic islets were characterized by a decrease in the area and number of islets due to the loss of β-cells, edema, changes and loss of clarity, the form of islets, in the groups of mature and elderly rats – existing areas of necrosis. In young rats, pathological changes were less pronounced due to anatomical features (better blood supply, relatively more number of pancreatic acinusis). Histological picture of preparations of the pancreatic gland in rats of mature and elder rats indicated a marked insufficiency of the insulatory apparatus.