MORPHOFUNCTIONAL STATE OF PANCREAS IN RATS WITH DIABETES MELLITUS

Abstract

Goal. To analyze the literature sources concerning morphofunctional state of a pancreas in case of diabetes mellitus and treatment in white laboratory rats. Materials and methods. Generalisation of ukrainian and foreign literature data, results of meta-analyses and randomized studies. Results. Characteristics of main mechanisms of diabetes mellitus modeling was conducted in experimental animals. Literature data regarding the peculiarities of pancreatic islets in normal conditions, in case of diabetes mellitus and pharmacological correction of this disease were intensified. Anatomically, pancreas is divided into three regions: duodenal, gastric and splenic. This division in rats is somewhat conditional due to small size of organ. In some cases, highest concentration of endocrine islets is found in splenic region of gland. Islets are formed by endocrinocytes. There are four types of endocrine cells in rats: insulinocytes, glucagonocytes, somatostatinocytes and pancreatic polypeptide cells. In rats with diabetes, morphofunctional state of pancreas worsens. Numbers of insulinocytes and area of ​​islets are decreases, level of glucose and glycosylated hemoglobin increases. Review of literature sources shows social significance of conducted research, as experimental diabetes mellitus creates discomfort and reduces the quality and lifespan of experimental animals. Prolonged uncorrected hyperglycemia creates the background for micro- and macroangiopathies development. Pharmacotherapy for diabetes primarily aims to achieve normoglycemia through dietary correction in combination with pharmacological agents. This not only slows down the progression of diabetic micro- and macroangiopathies but also extends the lives of rats. In context of absolute insulin deficiency, a priority for correcting streptozotocin-induced diabetes remains using of insulin therapy with exogenous insulin drugs and enhancing reparative processes in the gland due to improved regeneration of endocrinocytes. The priority task for scientists still remains the development of medicines capable of promoting regeneration processes of islets. According to literature sources, polytherapy of diabetes mellitus using pharmacological antidiabetic drugs can be more effective as compared to monotherapy. Several authors have studied the combined effect of insulin and exenatide (an incretin mimetic), finding that exenatide enhances the regenerative capabilities of pancreatic islets in diabetes mellitus. However, the use of incretin mimetics in type І diabetes mellitus remains controversial and requires further study. Expediency of experimental diabetes mellitus modeling is based on developing new methods for type І diabetes mellitus correction. This will promote prolonged functioning of endocrine cells, enhance regeneratory and compensatory processes in pancreas and optimize the therapeutic effect of antidiabetic drugs in experiment. Conclusion. The presented data establish the peculiarities of morphological changes in pancreatic islets in pathogenesis of diabetes, confirm the necessity of pharmacological correction of streptozotocine-induced diabetes in experimental animals by normalizing carbohydrate metabolism, activating compensatory-recovery processes and regenerations of islets with the help of nutrition and treatment. Comprehensive polytherapy and normalization of nutrition allow for the slowing of the development of diabetic micro- and macroangiopathies and cardiovascular events in the context of diabetes.