Effects of various prostanoids on the in vitro metabolism of bovine articular chondrocytes.

The dose-dependent effects of 9 prostanoids (PGA1, PGA2, PGE1, PGE2, PGF1 alpha, PGF2 alpha, PGD2, PGI2, 6 keto-PGF1 alpha) on metabolism of cultured bovine articular chondrocytes were investigated. Most prostanoids dose-dependently inhibited 35SO4= and 3H-glycine incorporation. At 25 microgram/ml, the inhibitory sequence was A2 greater than or equal to D2 greater than E2= E1 = A1 greater than 6 keto-F1 alpha greater than F1 greater than F2, but sensitivity (lowest dose eliciting inhibition) followed the sequence E2 greater than 6 keto-F1 alpha = F1 greater than A2 = D2 greater than E1 greater than A1. At 25 microgram/ml, PGA2 also inhibited incorporation of 3H-cytidine and 3H-thymidine, but had no significant effect on 3H-glucose or 14C-xylose incorporation. The inhibitory effect of PGA2 was apparent after 30 minutes exposure for 35SO4= and after 60 minutes for 3H-cytidine, and was still present up to 72 hours following incubation in fresh non-PG-containing medium. PGI2 had no significant effect on 35SO4= incorporation but at concentrations below 10 microgram/ml enhanced uptake of 3H-glycine. The PG-induced inhibitory effect was apparently not due to cell damage as indicated by measurement of 3H-glucose metabolism and lactate production.