Study of the neurological mechanisms of referred pain of chronic prostatitis and its relationship with the bladder and the pelvic floor / 解放军医学杂志

ABSTRACT

Objective To look for the neurological evidence of the referred pain of the chronic prostatitis and the relationship between the pain of the chronic prostatitis, bladder, and pelvic floor. Methods The distribution of plasma extravasation was determined with Evans blue dye after irritation of the prostate and bladder of the SD rat with capsaisin, and the distribution of dye extravasation was analyzed. Substance P expression within the dorsal horn of the spinal cord was determined by hybridization in situ after irritation of the prostate, bladder and superficial somatic region of the pelvic floor with formalin. Results Pain irritation of the prostate resulted in plasma extravasation in L_5 to S_2 dermatomes (mainly in L_6 to S_1). In rats receiving bladder irritation, the distribution of plasma extravasation showed a similar pattern to that observed in rats receiving prostatic irritation. Irritation of the prostate, bladder and pelvic floor resulted in similar substance P expression within the dorsal horn of the spinal cord (L_6 to S_1). Conclusions Our results strongly suggest that referred pain status in inflammation of the bladder and prostate is neurogenically mediated. There are significant overlaps of nociceptive neurons within the spinal cord, which receive nociceptive inputs from the prostate, bladder and pelvic floor. Pathological changes in the prostate, bladder and pelvic floor can result in similar pain sensations.