[In vitro effects of diclofenac and selective cyclooxygenase-2 inhibitors on prostaglandin release from inflamed bursa subacromialis tissue in patients with subacromial syndrome].

BACKGROUND

To compare the in vitro effects of selective COX-2 inhibitors (L-745,337, NS-398 and DFU) and of COX-unspecific diclofenac on release of PGE(2 )and 6-keto-PGF(1alpha) from inflamed bursa subacromialis tissue (IBST) obtained from a total of 35 patients with shoulder impingement syndrome (SIS).

PATIENTS AND

METHODS

Bursal specimens were incubated in the presence of drugs (0.01-1000 microM) for 20 min and 16 h.

RESULTS

After 20 min 10 microM diclofenac significantly inhibited formation of PGE(2) and 6-keto-PGF(1alpha), whereas L-745,337 and NS-398 (10-1000 microM) induced significant inhibition only at concentrations > or =100 microM. In contrast to equimolar diclofenac, DFU (0.01-10 microM) induced no inhibition of bursal PGE(2) release but a dose-dependent, although statistically not significant inhibition after 16 h. The inhibitory potency of diclofenac (0.01-10 microM) was even more increased during long-term incubation showing greater inhibition than DFU at all concentrations studied.

CONCLUSION

The data suggest that in IBST in SIS in vitro the majority of PG is generated via the COX-1 pathway.