Glyphosate-based herbicide (GBH) exposure is known to have adverse effects on endocrine-related tissues. Here, we aimed to determine whether early postnatal exposure to a GBH induces long-term effects on the rat mammary gland. Thus, female Wistar pups were injected with saline solution (Control) or GBH (2 mg glyphosate/kg/day) on postnatal days (PND) 1, 3, 5 and 7. At 20 months of age, mammary gland samples were collected to determine histomorphological features, proliferation index and the expression of steroid hormone receptors expression, by immunohistochemistry, and serum samples were collected to assess 17β-estradiol (E2) and progesterone (P4) levels. GBH exposure induced morphological changes evidenced by a higher percentage of hyperplastic ducts and a fibroblastic-like stroma in the mammary gland. GBH-treated rats also showed a high expression of steroid hormone receptors in hyperplastic ducts. The results indicate that early postnatal exposure to GBH induces long-term alterations in the mammary gland morphology of aging female rats.

中文翻译：

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草甘膦除草剂可诱导衰老 Wistar 大鼠的乳腺导管增生。


众所周知，接触草甘膦除草剂 (GBH) 会对内分泌相关组织产生不利影响。在这里，我们的目的是确定出生后早期接触 GBH 是否会对大鼠乳腺产生长期影响。因此，雌性 Wistar 幼崽在出生后第 1、3、5 和 7 天（PND）注射盐水溶液（对照）或 GBH（2 毫克草甘膦/千克/天）。在 20 个月大时，收集乳腺样本通过免疫组织化学测定组织形态学特征、增殖指数和类固醇激素受体的表达，并收集血清样本以评估17β-雌二醇（E2）和孕酮（P4）水平。 GBH 暴露引起形态学变化，表现为乳腺中增生性导管和成纤维细胞样基质比例较高。 GBH 治疗的大鼠在增生性导管中也表现出类固醇激素受体的高表达。结果表明，出生后早期接触 GBH 会引起老年雌性大鼠乳腺形态的长期改变。