Speckle-contrast imaging of pathological tissue microhemodynamics in the development of various diabetes models

摘要

The study of blood microcirculation is one of the most important problems of the medicine. This is caused by the fact that many diseases, such as cardio-vascular diseases, atherosclerosis, diabetes, chronic venous insufficiency, oncology diseases, cause functional and morphological changes of microcirculation of blood flow. The results of experimental study of changes of blood microcirculation of pancreas in rats with diabetes measured by using Laser Speckle Contrast Imaging (LSCI) at application of optical clearing agents are presented. Laser speckle contrast techniques are based on the spatial and temporal statistics of the speckle pattern, calculating of contrast of time-averaged dynamic speckles in dependence on the exposure time at the registration of the speckle-modulated images. In research, 38 Wistar rats weighing 300-500 g were used. Alloxan induced animal model and streptozotocin model of diabetes was explored. The influence of solution of glycerol, Omnipaque®-300 was investigated. Application of 70%-aqueous glycerol solution demonstrates 50%-decrease of blood flow velocity in the group of aloxan diabetic animals, to 10th min blood flow velocity was completely restored. In a group of animals with streptozotocin diabetes, the blood flow rate decreased by 54%, by 10 minutes the speed did not reach the initial value. Blood flow in the control group almost stopped, to 10 min has not recovered. Application of Omnipaque®-300 demonstrates 65%-increase of blood flow in the group of alloxan diabetic animals and an increase of bloode flow in the first 2 minutes of applying the solution by 45%. In both cases to 10th min, blood flow velocity was completely restored. Blood flow in the control group did not show any noticeable changes.