Сomparison of efficiency of methylene blue preparations for visualization of lymph drainage pathways in the experiment

Objective. To compare and evaluate the effectiveness of using methylene blue solutions to visualize lymph drainage pathways in laboratory animals (outbred rat). Materials and methods. In the experiment, 16 female outbred rats aged about 40 days, with an initial body weight of 180-220 g, kept in standard vivarium conditions, were used. Zolazepam (Zoletil®100) was used for anesthesia. Animals were randomized into 2 groups ― 8 in each. The first group was injected subcutaneously in the left thigh with a 1% aqueous solution of methylene blue, the second group ― solution of methylene blue with human serum albumin. Depending on the time of exposure, animals were divided randomly into 4 subgroups ― 15, 30, 45 and 60 minutes. There was evaluated the effectiveness of marking the lymph drainage pathways from the injection site. Results. The study demonstrated that the use of a 1% aqueous solution of methylene blue solution allows visualizing of the lymph drainage pathways when the preparation is exposed for 30 minutes. Staining of the lymph nodes of the next order occurs with an increase in exposure time. A solution of methylene blue in combination with human serum albumin stains the first node in the lymph drainage path 30 minutes after administration. The preparation is characterized by slow migration from the first-order lymph nodes (>60 minutes). Conclusion. The use of methylene blue solution in combination with serum albumin is characterized by slow migration from the first-order lymph nodes, which makes its use preferable for surgical interventions.