THE EFFECT OF TRINITROBENZENE SULFONIC-ACID ON GUT-DERIVED SMOOTH-MUSCLE CELL ARACHIDONIC-ACID METABOLISM - ROLE OF ENDOGENOUS PROSTANOIDS

The contribution of smooth muscle cells as a potential source of eicos anoid production during inflammatory states remains to be elucidated, We investigated the effect of trinitrobenzene sulfonic acid (TNB), a k nown pro-inflammatory agent, on jejunal smooth muscle cell eicosanoid production, Human gut-derived smooth muscle cells (HISM) were incubate d with TNB for 1 hour, Additionally, some cells were preincubated with either dimethylthiourea, or indomethacin for 1 hour before exposure t o identical concentrations of TNB. Incubation with TNB led to signific ant increases in PGE(2) and 6-keto PGF-1(alpha) release, but not leuko triene B-4 release; responses which were both inhibited by dimethylthi ourea and indomethacin treatment, Our results suggest that gut-derived smooth muscle cells may represent an important source of proinflammat ory prostanoids but not leukotrienes during inflammatory states of the intestine, The inhibition of prostanoid activity by thiourea may be m ediated by suppression of cyclooxygenase activity in this cell line.