The effects of sex hormones and prostaglandins to the tissue mast cells are variable by the animal species and tissue examined. While there are reports that the thymus has a certain control mechanism of the tissue mast cells, studies concerning effects of sex hormones and prostaglandins on mast cell of the thmus are rare. The purpose of this study is to understand influences of sex hormones to the effect of prostaglandin Fza on thymic mast cell in animal model.
Two hundred female adult albino rats, weighing 150 gm. in average, were subjected to bilateral oophorectomy to eliminate the effects of sex hormones from ovaries, and subsequently sex hormones and prostaglandin Fza were subcutaneously injected.
Five rats in each group were sacrificed daily on to 5 days after injections. Obtained tissue was processed by usual paraffin sectioning and stained with Radden´s modified toluidine blue staining method. The total numbers of mast cells in 30 high power fields (X400) were counted and findings in each group were compared.
The results obtained are as follows;
1. The numbers of mast cells in oophorectomized control group were in the range of from 71.57.9 to 92.52.1 throughout the experimental period, and there was no significant change with time interval.
2. In estrogen injected group, the numbers of mast cells showed maximum (150.640.6) at the first day after injection, and then continuously decreased to the level of 111.29.0 at the fifth day after injection.
3. In progesterone injected group, the number of mast cells were in the range of from 83.6 19.0 to 102.69.4 throughout the experimental period, similar with findings of the control group.
4. In testosterone injected group, the numbers of mast cells were in the range of from 62.3 14.6 to 76.013.0, which were lower than those of the control group.
5. In prostaglandin Fla injected group, the numbers of mast cells were 94.814.2 at the first day after injection and shoved increasing pattern throughout the experimental period, reaching the maximum numbers (111.817.8) at the fifth day after injection.
6. In the combined estrogen and prostaglandin Fsa group, the numbers of mast cells were 105.813.3 at the first day after injection and showed continuously increasing pattern, with the maximum numbers (131.617.8) at the fifth day after injection. This finding suggests that the estrogen has an effect of increasing the action of prostaglandin Fz. on the number of tissue mast cell in rat thymus about 20% in degree.
7. In the combined progesterone and prostaglandin F=a group, the numbers of mast cells ranged from 82.814.7 to 93. Y=7.2, and reflect that progesterone acts as an antagonistic mechanism to the effect of the prostaglandin Fz. on the thymic mast cell.
8. In the combined testosterone and prostaglandin Fz group, the numbers of mast cells at the first day after injection were 109.56.8 and increased throughout the experimental period. It seems that testosterone acts synergistically with prostaglandin F2 on the number of mast cell in rat thymus.
|