Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Tlaxcala, México.
Programa Educativo de Química Clínica, Facultad de Ciencias de la Salud, Universidad Autónoma de Tlaxcala, Tlaxcala, México.
Gynecol Endocrinol. 2021 Jun;37(6):528-533. doi: 10.1080/09513590.2021.1875427. Epub 2021 Jan 27.
To determine the role of estrogens in myofiber cross-sectional area (CSA) of the pubococcyegeus (Pcm) and iliococcygeus muscles (Icm).
In Experiment 1, we excised the Pcm and Icm during the metestrus and proestrus stages of the estrous cycle to measure the myofiber CSA. In Experiment 2, we allocated other rats into the following groups: sham (Sh), ovariectomized (OVX), OVX plus 1,4,6-androstatriene-3,17-dione (ATD; OVX + ATD), an aromatase inhibitor, and OVX plus estradiol benzoate (OVX + EB). We carried out appropriate statistical tests to determine significant differences ( ≤ 0.05) in variables measured for both Experiments.
The Pcm myofiber CSA at proestrus was higher than at metestrus, while the Icm myofiber CSA did not change. Ovariectomy increased the Pcm myofiber CSA, which was exacerbated with the ATD administration. The EB supplementation successfully reversed the ovariectomy-induced enlargement of the CSA. No significant changes were detected for the Icm myofiber CSA.
Fluctuating ovarian steroid levels at the estrus cycle significantly influence the CSA myofiber of the Pcm but not that of the Icm. Estrogen actions, having a gonadal or extragonadal origin, influence importantly the CSA of the Pcm.
确定雌激素在耻尾骨肌（Pcm）和髂尾骨肌（Icm）肌纤维横截面积（CSA）中的作用。
在实验 1 中，我们在发情周期的动情前期和动情期切除 Pcm 和 Icm，以测量肌纤维 CSA。在实验 2 中，我们将其他大鼠分配到以下组：假手术（Sh）、卵巢切除（OVX）、卵巢切除加 1,4,6-雄三烯-3,17-二酮（ATD；OVX+ATD）、芳香酶抑制剂和苯甲酸雌二醇（OVX+EB）。我们进行了适当的统计检验，以确定两个实验中测量的变量有显著差异（≤0.05）。
动情期 Pcm 肌纤维 CSA 高于动情前期，而 Icm 肌纤维 CSA 不变。卵巢切除增加了 Pcm 肌纤维 CSA，而 ATD 给药则加剧了这种情况。EB 补充成功逆转了 CSA 增大。Icm 肌纤维 CSA 没有明显变化。
发情周期中卵巢类固醇水平的波动显著影响 Pcm 的 CSA 肌纤维，但不影响 Icm。具有性腺或性腺外起源的雌激素作用对 Pcm 的 CSA 有重要影响。
