Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2004;26(8):595-602
DOI 10.1590/S0100-72032004000800002
PURPOSE: to evaluate the effects of estradiol benzoate associated with dexamethasone on the squamocolumnar junction (SCJ) of rats in permanent estrus (PE) and then ovariectomized (Ovx). METHODS: thirty female rats were divided into six groups of five animals each: PhEG rats in physiological estrus (PhE) treated with propylene glycol (vehicle); OVXG rats in PhE, Ovx and treated with vehicle; PEG - rats in PE treated with vehicle; PEOVXG rats in PE, Ovx and treated with vehicle; ESTRG rats in PE, Ovx and treated with 10 mg per day benzoate of estradiol, and DEXAG in PE, Ovx and treated with 10 mg per day estradiol benzoate associated with 0.8 mg dexamethasone. PE induction was performed with 1.25 mg testosterone propionate per animal per day after birth. After 90 days, rats in the OVXG, EPOVXG, ESTRG, and DEXAG groups were ovariectomized. After 21 days of castration, all animals received the corresponding treatment for five days. At the end of the experiment, all animals were sacrificed and the uteri removed for histological routine. RESULTS: the borders of the SCJ in the PEG were irregular and not clearly delineated, with many buds towards the direction of the lamina propria as well as a reduction in the leukocyte number compared to the PhEG. The SCJ of the OVXG and PEOVXG was not very visible, with cubical epithelium on the endometrial side and with reduction in the layers of squamous epithelium due to stromal atrophy. The SCJ in the ESTRG was more developed than in the OVXG and PEOVXG, but it was similar to that of the PEG, having unclear borders. In contrast, the SCJ of the DEXAG was well-delineated and similar to the PhEG. CONCLUSION: our data suggest that estrogen associated with dexamethasone may be important for remodeling SCJ morphology in female rats with previously induced permanent estrus and subsequent ovariectomy.