NEUROGENIC INFLAMMATION OF GUINEA-PIG BLADDER

CAPSAICIN, substance P, and ovalbumin, instilled into the bladders of naive and ovalbumin (OVA) sensitized guinea-pigs caused inflammation, as indicated by increased vascular permeability. Histological changes after exposure to these compounds progressed with time form intense va sodilation to marginalization of granulocytes followed by interstitial migration of leukocytes. In vitro incubation of guinea-pig bladder ti ssue with substance P and ovalbumin stimulated release of prostaglandi n D2 and leukotrienes. In vitro incubation of bladder tissue with caps aicin, OVA, prostaglandin D2, leukotriene C4, histamine, or calcium io nophore A-23587 all stimulated substance P release. These data suggest that bladder inflammation initiated by a variety of stimuli could lea d to a cyclic pattern of release of inflammatory mediators and neurope ptides, which could result in amplification and persistence of cystiti s after the inciting cause has subsided.