Effect of cellular growth state on indices of n - 6 polyunsaturated fatty acid status in human fibroblasts.

A 2 x 2 design was employed to examine the effect of cellular growth state and medium serum concentration on potential indices of n - 6 polyunsaturated fatty acid (PUFA) status in human skin fibroblasts. The cells were cultured either as nonmultiplying cell monolayers or as medium-density, log-phase multiplying cells. An interaction of cellular growth state and medium serum concentration influenced the accumulation of 20:3(n - 9), but not 22:3(n - 9), in the cellular phospholipids. The 20:3(n - 9)/20:4(n - 6) ratio was the most sensitive index of n - 6 PUFA status; however, the ratio was significantly affected by cellular growth state. The 22:3(n - 9)/22:4(n - 6) ratio appears to be an index of n - 6 PUFA status in fibroblasts that is not significantly affected by the growth state of cells.