[Ultrastructural modifications of the bladder wall in senescence]

Histochemical and ultrastructural studies of the epithelial, muscular, connective, vascular and nervous tissue layers have been carried on endoscopic or surgical biopsies in patients from 23 to 92 years old. Beyond 70 years old, the junctional complexes between the superficial cells of the epithelium are altered and the number of intracellular organelles is diminished. The intercellular spaces and binds between the muscle cells are modified. Some interstitial fibrosis occurs and the density of the connective tissue increases. The authors describe also similar observation in the bladder wall of the old rats. An arteriosclerosis of small vessels is observed. The density of the autonomous nervous network is reduced and the cholinergic innervation becomes preponderant. No specific ultrastructural modification of the nerves is seen except a neuromuscular infiltration by a conjunctive hyperplastic tissue. These morphological changes can be related to some modifications of the vesical compliance.