Evaluation of some factors of the phagocytic and lymphoid resistance systems in the blood of male laboratory rats

Objective : evaluation of some factors of the phagocytic and lymphoid resistance systems in the blood of male laboratory rats. Materials and methods . The experimental part was carried out on a group of 7 male Wistar laboratory rats. The experiment was conducted in three stages, corresponding to the two-, three-, and four-month ages of the males. At each stage, samples of venous blood were collected and analyzed for the absolute number of leukocytes and their populations. The analysis of T- and B-lymphocytes was performed using the method of cytochemical determination of non-specific esterase. Leukograms were obtained at each stage of the experiment, and leukocyte indices were calculated based on the data obtained. Results . At the end of the experiment, the predominance of resistance factors of the lymphoid system was noted. Thus, the relative number of lymphocytes was in the range from 74,20±1,56 % to 75,40±1,86 %. The ratio of T- and B-lymphocytes throughout the experiment ranged from 54,80±1,39 % to 45,20±1,39 % to 57,40±1,36 % to 42,60±1,36 %. When assessing leukocyte indices, a low value of the neutrophil-lymphocyte ratio index (in the range of 0,28±0,03 to 0,29±0,03) and a high value of the Garkavi index (at least 4,18±0,48) were found. Conclusion. The leukogram of rats is characterized by a predominance of lymphocytes, which determines a higher activity of the factors of the lymphoid system of resistance. Nevertheless, it is assumed that rats can have a very rapid mobilization of neutrophils and monocytes from the bone marrow and marginal pool in response to infection, which provides a high efficiency of the phagocytic system, despite its low number in the circulating blood. It is important to note that T-lymphocytes are the predominant population of lymphocytes, while B-lymphocytes normally make up a smaller portion. The study of integral hematological indices allowed to establish the prevalence of humoral resistance over cellular, as well as a higher activity of the effector link of immunity.