Effects of dichloroisoproterenol on macromolecular synthesis and differentiation in Tetrahymena vorax

The effect of dichloroisoproterenol on macrostomal cell formation in Tetrahymena vorax was examined and the drug was found to be 50% inhibitory at a concentration of 88 microM. Cellular uptake and incorporation of a variety of radiolabelled precursors was monitored in the presence of dichloroisoproterenol. The results demonstrate a strong, concentration-dependent inhibitory effect on RNA and protein biosynthesis, with a lesser inhibition observed for lipid biosynthesis. These data indicate that dichloroisoproterenol's reported effects on vacuole formation and processing in Tetrahymena are nonspecific with regard to phagocytic processes, but result from a general suppression of macromolecular synthesis.