Stress stimuli and the prostatic gland--an experimental study in the rat.

A suggested relationship between stress stimuli--a reduced prostatic blood flow--and non-acute prostatitis, was investigated. Blood flows in the major genital organs of male Sprague-Dawley rats were measured after they had been subjected to standardized experimental short-term and protracted (10 days) stress stimuli. The blood-flow measurements were made by means of a radioactive microsphere method. The used stress stimuli reduced the prostatic blood flow by approximately 50 per cent. As compared with a control group, plasma testosterone concentrations, were reduced in rats submitted to stress stimuli for 10 days. Inflammatory histopathological changes and large numbers of inflammatory cells were seen in the prostatic glands of rats submitted to stress stimuli for 10 days. The findings were in accordance with those considered as characteristic for non-acute prostatitis in man. No corresponding changes were observed in a control group. There was no evidence indicating a bacterial infection. The inflammatory manifestations predominated in the ventral lobes while the dorsolateral ones were almost unaffected. The ventral lobes of the rat prostate have a less advanced drainage system and a lower zinc content than the dorsolateral lobes. The results verify a causal connection between protracted experimental stress stimuli and an inflammatory reaction in the prostatic gland in rats. The mechanism may be a stress stimuli induced decreased blood perfusion of the gland. Stress stimuli seem to be of importance in the pathogenesis of non-acute prostatitis in man.