Correlation of beta-endorphin and prostaglandin E2 levels in prostatic fluid of patients with chronic prostatitis with diagnosis and treatment response.

PURPOSE The chronic pelvic pain syndrome is a clinically defined symptom complex of unclear etiology. We have noted increased oxidative stress in the prostatic fluid of these patients, implying an active inflammatory response. Immune cells can produce the natural opioid beta-endorphin at the site of injury, which may modulate pain. We measured beta-endorphin and the inflammatory marker prostaglandin E2 in the expressed prostatic secretions of men with prostatitis, and correlated the results with symptoms. MATERIALS AND METHODS Expressed prostatic secretions samples from 70 patients and 8 asymptomatic controls were collected and frozen. beta-Endorphin and prostaglandin E2 were measured by enzyme-linked immunosorbent assay. Results were stratified according to prostatitis category and compared in individuals before and after therapy. RESULTS In symptomatic patients beta-endorphin and prostaglandin E2 were not significantly different in categories II, IIIa and IIIb expressed prostatic secretions but they were higher than in controls. The mean beta-endorphin level plus or minus standard error of mean in symptomatic patients was significantly higher (23.8 +/- 11 ng./ml. versus 8.7 +/- 4.7, p = 0.0001) and mean prostaglandin E2 was lower (6.01 +/- 2.9 ng./ml. versus 3.01 +/- 2.9, p = 0.001) after successful therapy with antibiotics or antioxidant phytotherapy, Prosta-Q (Farr Laboratories, Santa Clarita, California). CONCLUSIONS We observed a correlation of higher prostaglandin E2 and lower beta-endorphin in symptomatic men with chronic prostatitis. Increased oxidative stress and inflammation may induce prostaglandin E2 production that would inhibit beta-endorphin release. Treatment with therapeutic agents that decrease oxidative stress, such as antibiotics and antioxidant phytotherapy, may function at least partially by increasing beta-endorphin and decreasing prostaglandin E2.