Bladder defense mechanism.

In order for micro-organisms to infect the urinary tract they must adhere to the vesical mucosa so that they remain after voiding. Experiments in our laboratory demonstrated that the bladder has a self-protective mechanism capable of preventing bacterial adherence to the surface. Histochemical staining demonstrated that this substance is a mucopolysaccharide. Treatment of the mucosa with acid disrupted the protective layer and resulted in a 20 to 100-fold increase in bacterial adherence. Within 24 hours this layer reappeared and binding was again reduced to normal. This phenomenon was not related to microbial species or metabolic activity.