Sensitivity of different phases of the cell cycle to selected hepatotoxins in cultured liver-derived (BL9L) cells

Abstract

1. Many toxins are active against dividing cells and cytofluorometric analysis of synchronized dividing liver-derived (BL9L) cells has been employed to study the relative sensitivity of the G₁(G₀), S and G₂/M phases of the cell cycle to selected hepatotoxins.

2. The cytotoxic metal beryllium, which inhibits cell division, caused a specific block at the G₁ phase of the cell cycle.

3. Dehydroretronecine, an antimitotic metabolite of the hepatotoxic plant pyrrolizidine alkaloids, retarded progression of cells through the cell cycle with a consistent accumulation at the late S to G₂ phase.

4. Exposure of cells to aflatoxin B₁-8,9-epoxide, the putative carcinogenic metabolite of the hepatocarcinogen aflatoxin B₁, particularly during the early period of S phase, produced morphologically transformed cells.