REACTION OF THE LYMPHOID SPLENIC TISSUE IN WHITE MICE ON AMYLOIDOGENESIS

Abstract

The reaction of lymphoid splenic tissue of mice on albumin model of systemic amyloidosis (case group, N = 5) was studied and compared to a similar indicator of intact mice (N = 5). Paraffin sections of the spleen, stained with hematoxylin and eosin and Congo red, were microscoped in a regredient LED white light on "Lumam-4" microscope. The absolute area of lymphatic follicles (LFs), their diameters and the area of amyloid lesion were measured on microphotos obtained with the help of video-eyepiece Levenhuk C800 NG 8M in LevenhukLite program. The obtained data were used for calculating the indicators: the relative areas of amyloid lesion (SrelA)), the red (SrelKB) and the white (SrelBP) pulp, the red/white pulp index, LFs' ovalityindex. The number of LFs was counted in the field of vision at magnification of 100. The obtained data were processed using the methods of descriptive and variative statistics and presented in the form of M±m, where M is the mean, m is the standard deviation. Differences of the means were determined using z test. The morphological pattern of the spleen in intact mice corresponded to the histological norm. The wet mass of the spleen in intact animals was 0.75±0.01 g, no signs of amyloidosis were found. In the case group, the wet mass of the spleen increased to 2.2±0.06 g (p=0.000), SrelA was 33.85± 3.39%. The average number of LFs in the field of vision did not change. The diameters by the large and small axes differed by 18% in intact animals and by 6.6% in experimental ones (p=0.000). Respectively, the area of LFs decreased by 11.2% and the ovality index increased by 10.3% (p = 0.0066) in experimental mice. SrelKB and SrelBPdid not change during the formation of amyloidosis. But the Red/White Pulp Index increased by 59.2% (p=0.008). Simulation of amyloidosis in experimental animals was accompanied by a significant increase in the area of the red pulp and by a reduction in the area of white pulp. Thus, the calculated relative morphometric indicators are more informative than the directly measured initial data; the wet mass of the spleen during experimental amyloidosis formation significantly increases; the lymphoid tissue of the spleen readily responds to amyloidogenesis by the change in the ratio of the red and white pulp, as well as by the change in the shape and the area of the lymph follicles.