Efeitos de atrazina como desregulador endócrino na homeostase tecidual e nos perfis morfológico e esteroidogênico de testículos, dúctulos eferentes e próstata ventral de ratos adultos

• Ano de defesa: 2017
• Autor(a) principal: Elisângela Martins dos Santos
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; Brasil; ICB - INSTITUTO DE CIÊNCIAS BIOLOGICAS; Programa de Pós-Graduação em Biologia Celular; UFMG
• Palavras-chave em Português: Biologia Celular; Atrazina; Homeostase; Testículo; Próstata; Ratos Wistar
• Link de acesso: http://hdl.handle.net/1843/33759

Atrazine is a potent endocrine disruptor that affects testicular steroidogenesis, and causes transient increase in testicular weight followed by atrophy, besides reduction of 3β-HSD, decrease in testosterone and increase in estradiol levels, being postulated that aromatase may be a target of atrazine. It is not known whether the effects observed on the testis are reversible or permanent, nor whether these effects are primary or secondary to changes in postesticular segments, as the efferent ductules, what we aim to clarify in this study. For comparison purposes, we also evaluated the ventral prostate. Adult male Wistar rats receiving atrazine at the dosage of 200/mg/Kg for 7, 15, or 40 days were used. Additionally, we evaluated if the effects of atrazine in these target organs could be reversible after discontinuation of the exposure for a period of 75 days, period longer than the spermatogenic cycle of rats (58 days). The exposure to atrazine resulted in transient increased in testicular weight, luminal dilation, followed by seminiferous tubule atrophy, as well as 3β-HSD reduction and increase in aromatase in the Leydig cells. The testicular atrophy and 3β-HSD reduction were more pronounced after the recovery period, in contrast with aromatase that returned to control levels. Moreover, there was increase of 89%, 76%, and 42% in macrophages subpopulations ED1- /ED2+ resident, ED1+/ED2+ transitory and ED1+/ ED2- induced, respectively, which were positive for 3β-HSD, raising the possibility of their involvement on steroidogenesis. The exposure to atrazine resulted in mild effects on the ventral prostate, but remarkable morphological alterations on the efferent ductules and disruption on tissue homeostasis, coincident with increase in aromatase expression. These findings further emphasize that the testicular damages caused by atrazine may be irreversible even after a recovery period longer than the spermatogenic cycle, and suggest that at least part of the testicular effects of atrazine may be secondary to the alterations in the efferent ductules.