| Abstract: | The effect of 1-chloro-2,4-dinitrobenzene (DNB), sulfobromophtalein (BSP) and cyclohexene oxide (cho) on N-acetylpenicillamine (NAPA) potentiated biliary excretion of methyl mercury in rats pretreated with cho for liver glutathione (GSH) depletion, has been tested. DNB, BSP and cho depressed NAPA potentiation of methyl mercury excretion in bile, while simultaneously biliary sulfhydryl concentration increased, due mainly to a relatively large proportion of unchanged NAPA, being excreted in bile. The fact that relatively large amounts of unchanged NAPA are excreted in bile, without affecting mercury excretion, indicates that NAPA per se cannot carry methyl mercury from liver to bile. In addition to unchanged NAPA, bile collected after administration of NAPA and DNB or BSP contained relatively large amounts of GSH conjugates of DNB or BSP, respectively, together with smaller amounts of GSH and another methyl mercury carrying component. The data are interpreted as suggesting that NAPA potentiation of methyl mercury excretion in bile can be due to an increased availability of GSH. However, it cannot be excluded that methyl mercury carrying components other than GSH and NAPA appearing in bile upon NAPA administration could play a role in NAPA potentiation of methyl mercury excretion in bile. |
