Laboratorio de Fisiopatología Ovárica, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU - CONICET), Mendoza, Argentina.
Facultad de Ciencias Veterinarias y Ambientales, Universidad Juan Agustín Maza, Mendoza, Argentina.
Reprod Biol Endocrinol. 2018 Apr 10;16(1):35. doi: 10.1186/s12958-018-0353-y.
Allopregnanolone is a neurosteroid synthesized in the central nervous system independently of steroidogenic glands; it influences sexual behavior and anxiety. The aim of this work is to evaluate the indirect effect of a single pharmacological dose of allopregnanolone on important processes related to normal ovarian function, such as folliculogenesis, angiogenesis and luteolysis, and to study the corresponding changes in endocrine profile and enzymatic activity over 4 days of the rat estrous cycle. We test the hypothesis that allopregnanolone may trigger hypothalamus - hypophysis - ovarian axis dysregulation and cause ovarian failure which affects the next estrous cycle stages.
Allopregnanolone was injected during the proestrous morning and then, the animals were sacrificed at each stage of the estrous cycle. Ovarian sections were processed to determine the number and diameter of different ovarian structures. Cleaved caspase 3, proliferating cell nuclear antigen, α-actin and Von Willebrand factor expressions were evaluated by immunohistochemistry. Luteinizing hormone, prolactin, estrogen and progesterone serum levels were measured by radioimmunoassay. The enzymatic activities of 3β-hydroxysteroid dehydrogenase, 3α-hydroxysteroid oxidoreductase and 20α-hydroxysteroid dehydrogenase were determined by spectrophotometric assays. Two-way ANOVA followed by Bonferroni was performed to determine statistical differences between control and treated groups along the four stages of the cycle.
The results indicate that allopregnanolone allopregnanolone decreased the number of developing follicles, while atretic follicles and cysts increased with no effects on normal cyclicity. Some cysts in treated ovaries showed morphological characteristics similar to luteinized unruptured follicles. The apoptosis/proliferation balance increased in follicles from treated rats. The endocrine profile was altered at different stages of the estrous cycle of treated rats. The angiogenic markers expression increased in treated ovaries. As regards corpora lutea, the apoptosis/proliferation balance and 20α-hydroxysteroid dehydrogenase enzymatic activity decreased significantly. Progesterone levels and 3β-hydroxysteroid dehydrogenase enzymatic activity increased in treated rats. These data suggest that allopregnanolone interferes with steroidogenesis and folliculogenesis at different stages of the cycle.
Allopregnanolone interferes with corpora lutea regression, which might indicate that this neurosteroid exerts a protective role over the luteal cells and prevents them from luteolysis. Allopregnanolone plays an important role in the ovarian pathophysiology.
别孕烯醇酮是一种在中枢神经系统中独立于类固醇生成腺合成的神经甾体；它影响性行为和焦虑。本工作的目的是评估单次药理剂量的别孕烯醇酮对与正常卵巢功能相关的重要过程的间接影响，如卵泡发生、血管生成和黄体溶解，并研究在大鼠发情周期的 4 天内内分泌谱和酶活性的相应变化。我们假设别孕烯醇酮可能触发下丘脑-垂体-卵巢轴失调并导致卵巢衰竭，从而影响下一个发情周期阶段。
在发情前期的早晨注射别孕烯醇酮，然后在发情周期的每个阶段处死动物。对卵巢切片进行处理，以确定不同卵巢结构的数量和直径。通过免疫组织化学评估半胱天冬酶 3、增殖细胞核抗原、α-肌动蛋白和血管性血友病因子的表达。通过放射免疫测定法测量血清黄体生成素、催乳素、雌激素和孕酮水平。通过分光光度法测定 3β-羟甾脱氢酶、3α-羟甾氧化还原酶和 20α-羟甾脱氢酶的酶活性。采用双因素方差分析（ANOVA）和 Bonferroni 检验比较对照组和处理组在发情周期四个阶段的统计学差异。
结果表明，别孕烯醇酮减少了发育中的卵泡数量，而闭锁卵泡和囊肿增加，但对正常周期无影响。处理卵巢中的一些囊肿表现出类似于黄体化未破裂卵泡的形态特征。处理大鼠卵泡中的凋亡/增殖平衡增加。处理大鼠发情周期的不同阶段内分泌谱发生改变。血管生成标志物的表达在处理卵巢中增加。关于黄体，凋亡/增殖平衡和 20α-羟甾脱氢酶的酶活性显著降低。处理大鼠的孕酮水平和 3β-羟甾脱氢酶的酶活性增加。这些数据表明，别孕烯醇酮在周期的不同阶段干扰类固醇生成和卵泡发生。
别孕烯醇酮干扰黄体退化，这表明这种神经甾体对黄体细胞发挥保护作用，防止黄体溶解。别孕烯醇酮在卵巢病理生理学中起重要作用。
