Upregulation of TRPV1 in spinal dorsal root ganglion by activating NGF-TrkA pathway contributes to pelvic organ cross-sensitisation in rats with experimental autoimmune prostatitis

Chronic prostatitis/chronic pelvic pain syndrome (CP⁄CPPS) is the prostate gland inflammation characterised as genitourinary pain in the pelvic region. The rat experimental autoimmune prostatitis (EAP) was achieved to mimic CP⁄CPPS. The expressions of transient receptor potential vanilloid 1 (TRPV1) in the prostate, bladder and spinal dorsal root ganglion (DRG) were analysed by Western blotting. Tropomyosin receptor kinase A (TrkA) and nerve growth factor (NGF) in the DRG were also analysed by Western blotting. Measurements of inflammatory cytokines were carried out according to the instructions of the corresponding kits. The expressions of TRPV1 in the prostate, bladder and DRG in the EAP group were significantly higher than those in the control group. The expressions of NGF and TrkA in the DRG in the EAP group were significantly higher than those in the control group. The levels of serum TNF-α and IL-1β in the EAP group were significantly higher than those in the control group. We conclude that CP⁄CPPS may participate in the pathological activation of neurons in the L5-S1 segment of DRG by activating NGF-TrkA pathway and cause pelvic organ cross-sensitisation by upregulating the expression of TRPV1 in the prostate, bladder and DRG.