RESPONSE OF HUMAN GINGIVAL FIBROBLASTS TO PROSTAGLANDINS

The effects of various prostaglandins (PGs) on the functions of human gingival fibroblasts (Gin-1 cells; ATCC CRL 1292) were examined by pha se-contrast microscopy, cell-counting and radioautographic experiments . Tested PGs were PGA(1), PGA(2), PGB(1), PGB(2), PGD(2), PGE(1), PGE( 2), PGF(1) alpha, PGF(2) alpha, PGI(2), 6-keto-PGF(1) alpha, 9 alpha-1 1 alpha-methanoepoxy-PGF(2) alpha, and thromboxane (TX) B-2. PGA(1) an d PGD(2) at 30 mu M caused morphological deformation of Gin-1 cells. A ll the PGs tested at 30 mu M suppressed the proliferation of Gin-1 cel ls in the logarithmic growth phase. Furthermore, all the PGs tested at 10 mu M suppressed DNA synthesis, collagen synthesis, and noncollagen ous protein synthesis in confluent Gin-1 cells, while exerting no effe ct on GAG synthesis. The concentrations of PGs used are beyond those f ound in healthy gingiva. However, in periodontitis the local concentra tions of some PGs within the gingiva are expected to be extremely elev ated beyond the physiological level. These results suggest that PGs ma y play an important role as a negative regulator in metabolism and som e pathologic gingival conditions by suppressing the functions of gingi val fibroblasts.