The effect of uropathogenic bacteria on ureteral motility.

The effect of bacterial products of various strains obtained from patients with urinary tract infections was tested on peristalsis of sheep ureteral rings. In 55-70% spontaneous rhythmic contractions were inhibited by addition of small amounts of growth supernatants from Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. The isolates were also tested on mesenteric artery ring preparations. In these vessels the isolates induced tonic contractions, particularly when the vessel had been depolarised and precontracted with a 40 mM KCl solution. This response is characteristic of a calcium ionophore, known to occur in some bacterial toxins. The active principle of the bacterial ureteroplegic factor (BUF) is heat sensitive and distinct from endotoxins which speed up peristalsis. It is suggested that the ureteroplegic action depends on an exotoxin with ionophoric properties.