Cytotoxicity of bilirubin for human fibroblasts and rat astrocytes in culture. Effect of the ratio of bilirubin to serum albumin.

The sensitivity of rat brain astrocytes and human fibroblasts in culture to unconjugated bilirubin was investigated. Medium containing 6 mumol/1 bilirubin and increasing concentrations of human serum albumin giving ratios of 0.5-1.

Competitive inhibition of thyroid hormone uptake into cultured rat brain astrocytes by bilirubin and bilirubin conjugates.

Thyroid hormone (TH) metabolism is altered in cases of unconjugated hyperbilirubinemia. These effects might involve inhibition of TH uptake by their target cells. Astrocytes, which are in close contact with the membranes of brain capillaries, might be the first brain cells to come into contact with bilirubin.