Effects of ovariectomy and steroid hormones on vaginal smooth muscle contractility
Effects of ovariectomy and steroid hormones on vaginal smooth muscle contractility
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DOI：
10.1038/sj.ijir.3901138
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发表时间：
2004-01-01
影响因子：
2.6
通讯作者：
Traish, AM
中科院分区：
文献类型：
--
作者：
Kim, NN;Min, K;Traish, AM
研究了类固醇激素在调节阴道平滑肌收缩性中的作用。家兔保持完整或切除卵巢。2周后，动物连续输注溶媒或超生理水平的睾酮（100 μ g/天）或雌二醇（200 μ g/天），再持续2周。远端阴道组织用于评估器官浴中的收缩性，并通过组织学评估组织结构的变化。输注溶剂的卵巢切除动物表现出显著的肌层萎缩和上皮高度降低，导致阴道壁变薄。Escherichia coli输注增加上皮高度，与完整动物相当，但仅部分恢复肌层。相反，睾酮灌注完全恢复了肌层，但仅部分恢复了上皮高度。在用去甲肾上腺素收缩并用溴苄铵处理的阴道组织条中，电场刺激（EFS）引起频率依赖性松弛，该频率依赖性松弛用溶剂轻微衰减，用雌二醇显著抑制，用睾酮显著增强。VIP诱导的松弛略有衰减，从车辆和雌二醇输注组的组织，但增强了睾酮输注动物的组织。当数据被标准化为钾收缩时，EFS或外源性去甲肾上腺素引起的收缩在卵巢切除术或类固醇激素输注后没有显著改变。然而，输注睾酮的动物的组织对去甲肾上腺素产生了显著更大的收缩力。这些观察结果表明，类固醇激素可能是阴道组织结构和收缩性的重要调节剂。
The role of steroid hormones in regulating vaginal smooth muscle contractility was investigated. Rabbits were kept intact or ovariectomized. After 2 weeks, animals were continuously infused with vehicle or supraphysiological levels of testosterone ( 100 mug/day), or estradiol ( 200 mug/day), for an additional 2 weeks. The distal vaginal tissue was used to assess contractility in organ baths and changes in tissue structure were assessed by histology. Ovariectomized animals infused with vehicle exhibited significant atrophy of the muscularis and decreased epithelial height, resulting in thinning of the vaginal wall. Estradiol infusion increased epithelial height, comparable to that of intact animals, but only partially restored the muscularis layer. In contrast, testosterone infusion completely restored the muscularis layer, but only partially restored the epithelial height. In vaginal tissue strips contracted with norepinephrine and treated with bretylium, electrical field stimulation (EFS) caused frequency-dependent relaxation that was slightly attenuated with vehicle, significantly inhibited with estradiol and significantly enhanced with testosterone. VIP-induced relaxation was slightly attenuated in tissues from vehicle and estradiol-infused groups, but was enhanced in tissues from testosterone-infused animals. Contraction elicited by EFS or exogenous norepinephrine was not significantly altered with ovariectomy or steroid hormone infusion when data were normalized to potassium contraction. However, the tissue from testosterone-infused animals developed significantly greater contractile force to norepinephrine. These observations suggest that steroid hormones may be important regulators of vaginal tissue structure and contractility.