Three-dimensional organization of the pars fibroreticularis framework of the urethral wall in normal human prostates.

INTRODUCTION

Knowledge of the prostatic portion of the urethra is essential to the comprehension of urinary continence phenomena. However, there are only a small number of studies that have addressed this relationship and analyzed the ultrastructure of the prostatic urethra.

MATERIAL AND

METHODS

A three-dimensional analysis of the fibrous components and the extracellular matrix of the prostatic urethra in 10 normal humans was performed with a scanning electron microscope. The prostates were obtained from 10 men (18 to 30 years old) who had died from accidents. The specimens were fixated in a modified Karnovsky solution for 48 h at 4°C, washed in a sodium phosphate buffered solution (PBS) for 2 h at 4°C and then incubated in 40 ml of 2 M NaOH at room temperature for 8 days (cellular digestion). Afterwards, the three-dimensional organization of the prostatic urethra stroma was observed.

RESULTS

It was observed that the prostates had a narrowed fibrous septa which condensed and formed a network in order to support the submucosa. Furthermore, it was also observed that they formed a homogeneous fibrous layer (pars fibroreticularis), which lined the urethral wall.

CONCLUSIONS

Knowledge of the urethra composition is essential to understand the physiopathological aspects of urinary incontinence. Moreover, our results showed a great amount of connective tissue underlying the prostatic urethra wall.