Service d'Urologie, Transplantation Rénale et Andrologie, Centre Hospitalier Universitaire Rangueil, Toulouse, France.
J Sex Med. 2012 Feb;9(2):466-71. doi: 10.1111/j.1743-6109.2011.02559.x. Epub 2011 Dec 6.
Nitric oxide synthases (NOSs) and estrogen receptors are expressed in the female urethra.
We aimed to assess the impact of sildenafil on micturition behavior, urethral tone according to the hormonal status and to determine the implications of the neuronal isoform of NOS (nNOS).
Four-week-old C57/BL6 female mice were sham-operated or ovariectomized. Six weeks later, they were injected intraperitoneally by any combination of sildenafil, 7-nitroindazole (7-NI)-a potent selective nNOS inhibitor-or the corresponding vehicles. The mice were then subjected to micturition behavior and leak point pressure studies. Urethral histomorphometry was performed.
The main outcome measures were micturition behavior, leak point pressure, and histomorphometry.
In sham-operated and ovariectomized animals, sildenafil did not impact micturition, although it decreased urethral resistance 10-fold. nNOS inhibition by 7-NI reduced the number of micturitions and increased residual volume and leak point pressure. It abrogated sildenafil-induced drop in urethral resistances. Hormonal status did not influence the structure of the urethral layers.
Irrespective of the hormonal status, sildenafil decreased leak point pressure by a nNOS-mediated mechanism.
一氧化氮合酶（NOSs）和雌激素受体存在于女性尿道中。
我们旨在评估西地那非对排尿行为、根据激素状态的尿道张力的影响，并确定神经元型一氧化氮合酶（nNOS）的影响。
4 周龄 C57/BL6 雌性小鼠接受假手术或卵巢切除术。6 周后，它们通过西地那非、7-硝基吲唑（7-NI）-一种有效的选择性 nNOS 抑制剂-或相应的载体的任何组合进行腹腔内注射。然后对小鼠进行排尿行为和漏尿点压力研究。进行尿道组织形态计量学检查。
主要观察指标是排尿行为、漏尿点压力和组织形态计量学。
在假手术和卵巢切除动物中，西地那非不影响排尿，尽管它使尿道阻力降低了 10 倍。7-NI 抑制 nNOS 减少了排尿次数，增加了残余尿量和漏尿点压力。它消除了西地那非诱导的尿道阻力下降。激素状态不影响尿道层的结构。
无论激素状态如何，西地那非通过 nNOS 介导的机制降低漏尿点压力。
