Morphometric changes of cardiac mast cells in rats acutely poisoned by T-2 toxin

Wistar rats were treated with T-2 toxin (1 LD50; 0.23 mg/kg sc) and the surviving animals were sacrificed on days 1, 3, 5, 7, 14, 21 and 28 after treatment. At each time, control animals were sacrificed, too. Cardiac mast cells, previously stained by Giemsa method, were analyzed in whole visual fields, magnification x40. In the present study the following quantitative morphometric parameters of cardiac mast cells were evaluated: perimeter (P), area (A) and roundness (R). In the control groups of rats the majority of mast cells were small (P = 6.86 - 7.99 mm), hypogranular (A = 11.60 -14.30 mm2) and ovoid (R = 0.60 - 0.65 mm). Mast cells, with discrete granules, hypergranular, had significantly different quantitative parameters (P = 12.80 -14.90 mm; A = 16.70 -20.00 mm2; R = 0.35 -0.38 mm). The minority of mast cells, classified as degranulated, had a large (P=20.70-23.30 mm), irregular shape (A = 24.40 -30.90 mm2) and showed degranulation (R = 0.15 - 0.21 mm). In the heart of T-2 toxin-treated rats the quantitative parametar values of hypogranular mast cells and hypergranular mast cells were similar to the control group during the whole study. However, degranulated mast cells showed a significant increase in perimeter and area values (p<0.05), while their roundness was decreased (p<0.05) in comparison to the control groups of animals. It could be concluded that the chosen quantitative morphometric parameters of cardiac degranular mast cells are useful for the evaluation of the functional status of the rats' heart during acute T-2 poisoning. .