Synthetic glucocorticoids are often found in surface waters and can cause harmful effects to aquatic organisms such as amphibians. In this work we evaluated the effects of the drugs prednisone (PD) and prednisolone (PL) on developmental, molecular, blood, biochemical and histological markers. tadpoles were exposed for 16 days to environmentally relevant concentrations of 0, 0.1, 1 and 10 µg/L of both drugs. PD increased the transcript levels of the enzyme deiodinase III (), the hormones cortisol and T4 and delayed development. Changes in the thyroid gland occurred after tadpoles were exposed to both drugs, with a reduction in the diameter and number of follicles and an increase/or decrease in area. Also, both drugs caused a decrease in lymphocytes (L) and an increase in neutrophils (N), thrombocytes, the N:L ratio and lobed and notched erythrocytes. Increased activity of the enzymes superoxide dismutase, glutathione -transferase and glucose 6-phosphate dehydrogenase was observed after exposure to PD. Furthermore, both drugs caused an increase in the activity of the enzymes catalase and glutathione peroxidase. However, only PD caused oxidative stress in exposed tadpoles, evidenced by increased levels of malondialdehyde and carbonyl proteins. Both drugs caused an increase in inflammatory infiltrates, blood cells and melanomacrophages in the liver. Our results indicate that PD was more toxic than PL, affecting development and causing oxidative stress.

中文翻译：

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泼尼松和泼尼松龙对 Aquarana catesbeianus 蝌蚪发育、血液、生化和组织病理学标志物的影响

合成糖皮质激素通常存在于地表水中，可能对两栖动物等水生生物造成有害影响。在这项工作中，我们评估了药物泼尼松 (PD) 和泼尼松龙 (PL) 对发育、分子、血液、生化和组织学标志物的影响。蝌蚪暴露在环境相关浓度为 0、0.1、1 和 10 µg/L 的两种药物中 16 天。PD 会增加脱碘酶 III ()、激素皮质醇和 T4 的转录水平，并导致发育延迟。蝌蚪接触这两种药物后，甲状腺发生变化，卵泡直径和数量减少，面积增加/或减少。此外，这两种药物都会导致淋巴细胞 (L) 减少，中性粒细胞 (N)、血小板、N:L 比率以及叶状红细胞和缺损红细胞增加。暴露于PD后观察到超氧化物歧化酶、谷胱甘肽转移酶和葡萄糖6-磷酸脱氢酶的活性增加。此外，这两种药物都会导致过氧化氢酶和谷胱甘肽过氧化物酶的活性增加。然而，只有PD会对暴露的蝌蚪造成氧化应激，丙二醛和羰基蛋白水平增加就证明了这一点。这两种药物都会导致肝脏中炎症浸润、血细胞和黑色素巨噬细胞的增加。我们的结果表明，PD 比 PL 毒性更大，会影响发育并引起氧化应激。