File talk:Fetal corpus cavernosum and corpus spongiosum 01.jpg

Photomicrographs of collagen in the corpus cavernosum and corpus spongiosum (blue color) of fetal penis at different ages in weeks post-conception (WPC).

A) Corpus cavernosum, fetus of 13 WPC – arrows indicate small amount of collagen; B) Corpus spongiosum, fetus of 13 WPC; C) Corpus cavernosum, fetus of 22 WPC; D) Corpus spongiosum, fetus of 21 WPC; E) Corpus cavernosum, fetus of 32 WPC; F) Corpus spongiosum, fetus of 32 WPC. Masson's trichrome, X1000.

Modifications of Erectile Tissue Components in the Penis during the Fetal Period

PLoS One. 2014 Aug 29;9(8):e106409. doi: 10.1371/journal.pone.0106409. eCollection 2014.

Gallo CB1, Costa WS1, Furriel A1, Bastos AL2, Sampaio FJ1.

Abstract BACKGROUND: The penile erectile tissue has a complex microscopic anatomy with important functions in the mechanism of penile erection. The knowledge of such structures is necessary for understanding the normal physiology of the adult penis. Therefore, it is important to know the changes of these penile structures during fetal development. This study aims to analyze the development of the main components of the erectile tissue, such as collagen, smooth muscle fibers and elastic system fibers, in human fetuses. METHODOLOGY/PRINCIPAL FINDINGS: We studied the penises of 56 human fetuses aged 13 to 36 weeks post-conception (WPC). We used histochemical and immunohistochemical staining, as well as morphometric techniques to analyze the collagen, smooth muscle fibers and elastic system fibers in the corpus cavernosum and in the corpus spongiosum. These elements were identified and quantified as percentage by using the Image J software (NIH, Bethesda, USA). From 13 to 36 WPC, in the corpus cavernosum, the amount of collagen, smooth muscle fibers and elastic system fibers varied from 19.88% to 36.60%, from 4.39% to 29.76% and from 1.91% to 8.92%, respectively. In the corpus spongiosum, the amount of collagen, smooth muscle fibers and elastic system fibers varied from 34.65% to 45.89%, from 0.60% to 11.90% and from 3.22% to 11.93%, respectively. CONCLUSIONS: We found strong correlation between the elements analyzed with fetal age, both in corpus cavernosum and corpus spongiosum. The growth rate of these elements was more intense during the second trimester (13 to 24 WPC) of gestation, both in corpus cavernosum and in corpus spongiosum. There is greater proportional amount of collagen in the corpus spongiosum than in corpus cavernosum during all fetal period. In the corpus spongiosum, there is about four times more collagen than smooth muscle fibers and elastic system fibers, during all fetal period studied.

PMID 25170760