代谢
经皮给药比口服给药更能长时间抑制血浆丁酰胆碱酯酶活性。口服甲磷在消化道迅速代谢,直接转化为正丁基硫醇,或者经氧化转化为S,S,S-三丁基磷硫代硫酸盐。正丁基硫醇显然是导致晚期急性毒性效应的原因。经皮给药的甲磷在消化道未发生代谢,引起了延迟的神经毒性,但并未产生晚期急性效应。
TOPICAL ADMIN CAUSED MORE PROLONGED INHIBITION OF PLASMA BUTYRYLCHOLINESTERASE ACTIVITY THAN ORAL ADMIN. ORAL MERPHOS WAS RAPIDLY METABOLIZED IN GI TRACT DIRECTLY TO N-BUTYL MERCAPTAN OR FOLLOWING ITS OXIDATION TO S,S,S-TRIBUTYL PHOSPHOROTRITHIOATE. N-BUTYL MERCAPTAN APPARENTLY CAUSED THE LATE ACUTE TOXIC EFFECTS. TOPICALLY ADMIN MERPHOS, WHICH WAS NOT METAB IN GI TRACT, CAUSED DELAYED NEUROTOXICITY BUT DID NOT PRODUCE A LATE ACUTE EFFECT.
来源:Hazardous Substances Data Bank (HSDB)