抄録
Cyclooxygenase has two isozymes, a constitutive type (cyclooxygenase-1) and an inducible type (cyclooxygenase-2). The aim of the present study was to determine whether cyclooxygenase-2 is associated with the increased production in prostaglandin E2 in glomeruli by aggregated protein. Mice were injected with aggregated bovine serum albumin. Glomeruli were isolated using sieves and a magnet. Production of prostaglandin E2 was increased in glomeruli after injection of aggregated bovine serum albumin. RT-PCR analysis indicated enhanced expression of cyclooxygenase-2 mRNA in aggregated bovine serum albumin-loaded glomeruli. Western blotting analysis indicated an increase in cyclooxygenase-2 protein in glomeruli by aggregated bovine serum albumin. Glomeruli were incubated with indomethacin, NS-398 or niflumic acid in the presence of arachidonic acid. Indomethacin resulted in remarkable reduction of prostaglandin E2 levels in aggregated bovine serum albumin-loaded glomeruli. Niflumic acid also inhibited prostaglandin E2 production, and its inhibitory rate was more than that of NS-398. In conclusion, aggregated protein induces cyclooxygenase-2 in glomeruli, suggesting that cyclooxygenase-2 is involved in the process of disposal of aggregated protein in glomeuli.