DIFFERENTIAL RELEASE OF PROSTAGLANDINS AND LEUKOTRIENES BY SENSITIZEDGUINEA-PIG URINARY-BLADDER LAYERS UPON ANTIGEN CHALLENGE

The relative contributions of mucosal/submucosal and detrusor layers t o the release of inflammatory mediators were investigated in isolated, ovalbumin (OVA) sensitized guinea pig urinary bladders. Ovalbumin cha llenge of sensitized mucosa induced release of prostaglandins (PG): PG E(2), PGD(2) and PGF(2 alpha), in that order of magnitude. The total r elease of PGs was significantly higher from the mucosa/submucosa than from the detrusor/serosa. Under the same conditions, net release of le ukotriene (LT) was observed predominantly from the detrusor. The total amount of histamine released from the mucosa was greater than that fr om the muscle layer. These results indicate differential production an d release of inflammatory mediators from the mucosal/submucosal and de trusor smooth muscle layers. These results may have serious implicatio ns in disorders, such as interstitial cystitis, involving bladder muco sal damage. The cytoprotective effect of PGE(2) is likely to be lost w hen the mucosa is damaged, and LT release from deeper layers may contr ibute significantly to symptoms of bladder inflammation.