Submicroscopic changes of type I alveolocytes in the early stages of experimental diabetes mellitus

Abstract

Introduction: Diabetes is one of the leading medical and social problems of the national health systems worldwide. Objective: To study the dynamics of ultrastructural changes in type I alveolocytes in the early period of experimental diabetes mellitus. Methods: Experiments were carried out on 20 white male Wistar rats.Diabetes mellitus was induced by intraperitoneal injection of streptozotocin solution (`Sigma`, USA), diluted in 0.1 M citrate buffer with pH 4,5 in dose of 60 mg/kg of weight. Pulmonary tissue sample acquirement for electronic microscopic research was performed under thiopental narcosis after 14 and 28 days. The cuts were studied using electron microscope. Results: Conducted submicroscopic analysis, 14 days after beginning of the research, demonstrated in the most alveolocytes type I nucleus with a matrix of medium electron-optical density and uniform distribution of chromatin granules. The components of the Golgi apparatus and the granular endoplasmic reticulum were expanded slightly. Some mitochondria with an enlightened matrix were observed in several cells. Basal membrane was shown without special structural changes. With increasing duration of the research (28 days) the nucleus of alveolocytes type I were found round in shape and with marginal placement of chromatin granules. Cisterns and tubules of the Golgi apparatus and granular endoplasmic reticulum were expanded. The number of ribosomes on the membranes of the latter was reduced. Mitochondria were shown with an enlightened matrix in many cells. The basement membrane was locally thickened. Conclusions: 1. Experimental diabetes mellitus leads to disorders of the ultrastructural organization of type I alveolocytes. 2. The severity of changes in type I alveolocytes depends on the duration of diabetes.