Sekita K
Department of Legal Medicine, Shouwa University School of Medicine, Tokyo, Japan.
Nihon Hoigaku Zasshi. 1992 Feb;46(1):14-31.
The efficacy of 2-Pyridine aldoximide methiodide (PAM) for lethal acute poisoning by fenitrothion (FNT) was investigated in mice and dogs. Sumithion (FNT 51.7%, emulsifiers 12.5% and xylol 35.8%) was used as fenitrothion. 1. FNT at 1500 mg/kg was administered orally to mice. After ten minutes 50 mg/kg of PAM was injected once iv, and plasma, erythrocyte, brain, liver and kidney ChE activities were investigated 30 and 60 min later. Recovery in ChE activity was found in every organ but the brain at 30 min, but no efficacy of PAM was observed at 60 min. 2. After administering 1500 mg/kg of FNT orally to mice, the life-saving effect was studied from the changes in mortality due to variation of PAM route, dosage and number of administrations. With oral administration of 1500 mg/kg of FNT, 75 to 85% of the animals died. The mortality ranged from 80 to 95% when the animals received a single intravenous injection of 50 mg/kg of PAM between zero and 60 min following the FNT administration. Thus, a single intravenous administration of PAM at 50 mg/kg showed no life-saving effect on the animals given FNT. However, the mortality was reduced to 45% when the animals received repeated subcutaneous injections of 20 mg/kg of PAM at a 3-hr interval from just after administration of FNT over 24-hr. In other repeated subcutaneous injection experiments, the mortality ranged from about 55 to 65%. In any PAM-treated group, the survival time was prolonged. This life-prolonging effect was more marked in the case of repeated subcutaneous injections of PAM by 12-hr and even more by 24-hr, than in the case of a single intravenous injection. FNT treatment caused marked salivation and watery diarrhea, and PAM clearly inhibited these signs of the muscarinic action of FNT. There was a high relationship between this inhibitory effect of PAM on the muscarinic action and its life-prolonging or life-saving effect. 3. PAM (150 mg/animal/shot, iv) was given 12 or 13 times during 7 hr from 10 min (4 animals), 3 hr (1 animal) and 6 hr (2 animals) after administration of FNT at 150 mg/kg. The effects of PAM on survival, plasma ChE activity, plasma protein (TP) and hematocrit (Ht) values were examined. The 3 dogs given FNT alone all died within 53 hr of administration, whereas 6 out of 7 animals treated with PAM survived.(ABSTRACT TRUNCATED AT 400 WORDS)
在小鼠和犬中研究了2-吡啶甲醛肟碘甲烷（PAM）对杀螟硫磷（FNT）致死性急性中毒的疗效。使用速灭松（FNT 51.7%、乳化剂12.5%和二甲苯35.8%）作为杀螟硫磷。1. 给小鼠口服1500 mg/kg的FNT。10分钟后静脉注射一次50 mg/kg的PAM，30分钟和60分钟后检测血浆、红细胞、脑、肝和肾的胆碱酯酶（ChE）活性。30分钟时除脑外各器官的ChE活性均有恢复，但60分钟时未观察到PAM的疗效。2. 给小鼠口服1500 mg/kg的FNT后，通过改变PAM的给药途径、剂量和给药次数，从死亡率变化研究其挽救生命的作用。口服1500 mg/kg的FNT时，75%至85%的动物死亡。在FNT给药后0至60分钟内单次静脉注射50 mg/kg的PAM时，动物死亡率为80%至95%。因此，单次静脉注射50 mg/kg的PAM对给予FNT的动物无挽救生命的作用。然而，在FNT给药后立即开始，每隔3小时给动物重复皮下注射20 mg/kg的PAM，持续24小时，死亡率降至45%。在其他重复皮下注射实验中，死亡率约为55%至65%。在任何PAM治疗组中，存活时间均延长。与单次静脉注射相比，PAM重复皮下注射12小时甚至24小时时，这种延长生命的作用更明显。FNT治疗导致明显的流涎和水样腹泻，PAM明显抑制了FNT的这些毒蕈碱样作用迹象。PAM对毒蕈碱样作用的这种抑制作用与其延长生命或挽救生命的作用之间存在高度相关性。3. 在给予150 mg/kg的FNT后10分钟（4只动物）、3小时（1只动物）和6小时（2只动物）开始的7小时内，静脉注射PAM（150 mg/动物/次）12或13次。检测PAM对存活、血浆ChE活性、血浆蛋白（TP）和血细胞比容（Ht）值的影响。仅给予FNT的3只犬在给药后53小时内全部死亡，而7只接受PAM治疗的动物中有6只存活。（摘要截取自400字）
