Model of Experimental Cystitis in Albino Wistar Rats

Summary

Progesterone capronate facilitates vesical inflammation in albino Wistar rats after transurethral infection with a serum resistant strain of E. coli. This hormone has an anticholinergic side reaction and leads to dilatation and incomplete voiding of the bladder which has a mainly parasympathetic innervation. That effect of hormonal treatment is probably responsible for the high rate of bladder infections — the prerequisite to test antimicrobial drugs.

Pyelonephritis is given more interest in urinary tract infections than cystitis though bladder infections often cause pyelonephritis. Mechanisms leading to acute or chronic bladder infections are as yet not well understood. Experimentally the instillation of a bacterial suspension into the intact bladder does not establish infection. However, several authors succeeded by previous damaging the bladder in different ways in analogy to obstructive urinary tract infection. Besides chemical irritations of the mucous membrane with terpentine, alcoholic salicylic acid solution or xylol (Uebel 1965), mainly mechanical factors inducing a subacute to chronic disease were preferred (Rényi-Vámos and Horváth 1961; Prát et al. 1969).

In continuation of the findings of our team that esters of estradiol and progesterone were effective in facilitating renal infection in rats (Commichau 1971) we now investigated the hormonal influence on bladder infections. We found that progesterone kept up vesical inflammatory activity at least for 3 weeks, a prerequisite to test the therapeutic effect of antimicrobial drugs.