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.

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