Bernstein Center for Computational Neuroscience Berlin, Humboldt-Universität zu Berlin, Philippstrasse 13, Haus 6, Berlin, Germany.
Institute of Medical Psychology, Charité-Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117, Berlin, Germany.
Sci Rep. 2024 Oct 4;14(1):23060. doi: 10.1038/s41598-024-72898-8.
Even tough clitoris plays a critical role in female sexuality, we lack a precise understanding of qualitative and quantitative aspects of the innervation of the human clitoris. To address this issue, we dissected human clitorides from body donors and imaged them after staining with iodine with microCT for a macroscopic analysis. To resolve innervation patterns at the microscopic level we prepared thin sections of clitorides and stained them with trichrome azan to reveal the tissue structure combined with immunocytochemistry against Neurofilament H antibodies to reveal all axons and luxol blue labeling to reveal myelinated axons. We find the clitoral branch of pudendal nerve that innervates the clitoris not as single nerve, but as number of loose bundles. In the crus of the clitoris, about 12 such bundles can be recognized while about 32 bundles are present in the clitoral hemi-body. We counted on avarage 2917 axons in the crus of the clitoris (76% of which are myelinated) and 3137 axons in the hemibody of the clitoris (71% of which are myelinated). While the human clitoris receives only one third of the number of axons that innervate the human penis, an estimate of innervation density (per surface area) revealed that clitoris has approximately 6 times denser innervation compared to the penis. Thus, our study combines histology with microCT analysis provides detailed information on the number, myelination and innervation density of dorsal nerve of clitoris.
尽管阴蒂在女性性特征中起着至关重要的作用，但我们对人类阴蒂的神经支配的定性和定量方面缺乏精确的了解。为了解决这个问题，我们从尸体捐献者身上解剖了阴蒂，并在碘染色后使用 microCT 进行宏观分析。为了解决微观水平的神经支配模式，我们制备了阴蒂的薄切片，并使用三色 azan 染色来显示组织结构，结合针对神经丝 H 抗体的免疫细胞化学来显示所有轴突，并使用卢索蓝标记来显示有髓轴突。我们发现，支配阴蒂的阴部神经的阴蒂分支不是单一的神经，而是许多松散的束。在阴蒂的根部，大约可以识别 12 个这样的束，而在阴蒂的半体中存在大约 32 个束。我们平均在阴蒂根部计数到 2917 个轴突（其中 76%是有髓鞘的），在阴蒂半体中计数到 3137 个轴突（其中 71%是有髓鞘的）。尽管人类阴蒂接收的支配神经轴突数量仅为支配人类阴茎的神经轴突数量的三分之一，但对神经支配密度（每表面积）的估计表明，阴蒂的神经支配密度大约是阴茎的 6 倍。因此，我们的研究将组织学与 microCT 分析相结合，提供了关于阴蒂背神经的数量、髓鞘形成和神经支配密度的详细信息。
