Open AccessReversible effects of monothiol (D-penicillamine) and dithiol (dimercaptosuccinic acid) chelating compounds on methylmercury-inhibited choline acetyltransferase activity and high affinity choline uptake.
Author(s) -
Haruo Kobayashi,
Akira Yuyama,
Yoshiaki Tokonabe,
Naonori Matsusaka
Publication year - 1982
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.32.655
Subject(s) - chemistry , choline acetyltransferase , choline , chelation , biochemistry , dithiol , acetylcholine , pharmacology , biology , inorganic chemistry
The effects of thiol compounds on methylmercury chloride (MMC)-inhibited choline acetyltransferase (ChAT) activity and MMC-inhibited high affinity choline uptake of rat brain tissue were studied in vitro. D-penicillamine (D-Pc) and dimercaptosuccinic acid (DMS) reversed the MMC-inhibited ChAT activity dose-dependently. Equilibrium dialysis of MMC-inhibited ChAT against the buffer containing 10(-3) M D-Pc reversed the ChAT activity almost completely. The reversal effect of D-Pc (monothiol compound) on MMC-inhibited ChAT was significantly more potent than that of DMS (dithiol compound). D-Pc and DMS almost equally reversed the MMC-inhibited high affinity choline uptake by synaptosomes in a dose dependent fashion. Washing with a solution containing D-Pc or DMS equally reversed the MMC-inhibited high affinity choline uptake in a dose-dependent fashion. Neither D-Pc nor DMS could reverse the hemicholinium-3-inhibited high affinity choline uptake.