Age-related changes in the concentration of elastic fibers in different regions of the rabbit penis

Abstract

PURPOSE:To investigate whether elastic fiber content in the corpus cavernosum (CC), corpus spongiosum (CS) and tunica albuginea (TA) of the rabbit penis undergoes modifications with age. METHODS:Rabbits were sacrificed, in groups of ten animals each, at 30, 120, 240, and 730 days of age. Histological sections were obtained from the penile middle shaft and were stained with Weigert's resorsin fuchsin. The content of elastic fibers was determined using stereological methods, and was expressed as volume fraction. RESULTS:At 730 days of age, elastic fiber content was increased by 54% (p<0.004), 78% (p<0.004), and 87% (p<0.004) in the TA, CC, and CS, respectively, compared with animals aged 30 days. After 30 days of age, the concentration gradually and significantly increased until 240 days of age. In 730-day old animals, the concentration, compared with the previous age group, was unchanged in the CC and decreased by 20% (p<0.004) in the TA. CONCLUSIONS:Elastic fiber contents in the rabbit penis correlate with properties of penile tissues. Although after one month of age there is a gradual increase in these concentrations, in two-year old animals this trend is interrupted, which suggests that this could be an early alteration due to senescence.

Age-dependent histomorphometric evolution of the corpus spongiosum

“…However, no initial increase in elastic fibers was observed. This is different finding from Gallo et al 13 and Abidu-Figueiredo et al 14 , Gallo et al 13 studied the modifications of erectile tissue components in the penis during the fetal period in Humans, and showed a significant increase of the elastic and collagen fibers during the early stages of development of CS. Abidu-Figueiredo et al 14 studied rabbits penises from 30 to 730 days and found a progressive increase in the density of elastic fibers in the CS during the whole period.…”

Stereological analysis of elastic fibers of the corpus cavernosum of rats during the aging process

“…In diabetic rabbits, Abidu-Figueiredo et al . 9 observed a reduction in the Vv of elastic fibers of the corpus cavernosum despite the increase in smooth muscle fibers, which indicates that changes in the behavior of elastic fibers seem to be directly associated with the presence of pathological processes resulting in ED. Although it is not the main focus of this study to evaluate the penile functional change with age, the outstanding reduction of elastic fibers Vv in older rats allows us to infer that this reduction may be associated with the ED related to aging.…”

“…Few studies have addressed changes in the Vv of elastic fibers of the mammalian corpus cavernosum during the natural aging process. In rabbits, a progressive increase in the Vv of these fibers was observed between 30 and 240 days of life, and stabilization was observed between 240 and 730 days 9 . In humans and rats, the inverse effect is reported, with reduction of Vv with age 10 .…”

“…8 demonstrated the relevance of stereological analysis in determining the relative densities of muscle, collagen, and elastic fibers of the corpus cavernosum of rats at 4 months of age, as well as its effectiveness in describing the behavior of the corpus cavernosum extracellular matrix in pathological states. Also using stereology, Abidu-Figueiredo et al 9 proved the effects of diabetes mellitus on the corpus cavernosum of rabbits and showed the reduction of elastic fibers and collagen. In our experience, stereology is a reliable tool, the capacity to provide homogeneous positive test-points for rats at the same age, as well as the capacity to confirm our valid hypothesis in agreement with literature data, base this reliability.…”

“…Analysis of the points of interest of the images was based on the determination of the Vv of elastic fibers using the grid M42 9 , comprising 42 test points that were superimposed on the selected image ( Fig. 2 ).…”