| Abstract: | 戊乙醯去羥梔子甘(Penta-acetyl geniposide;(AC)/sub 5/GP)對黃麴毒素(Aflatoxin B/sub 1/;AFB/sub 1/)引起老鼠急性肝毒性有促進之作用;而對AFB/sub 1/引起老鼠慢性致癌作用則有抑制之趨向。 (AC)/sub 5/GP預先以胃管餵食三天或三小時,在以腹腔注射AFB/sub 1/(2mg/Kg body weight),則發現(AC)/sub 5/GP的添加會加強由AFB/sub 1/所引起老鼠肝毒性之強度,血清中Asparate aminotransferase(AST), Alanine aminotransferase(ALT), .gamma.-glutamyl transpeptidase(.gamma.-GT)及ALP之活性均較AFB/sub 1/單獨處理組明顯上升,表示老鼠肝臟受到傷害而釋放這些酵素至血清中。而肝臟中Glutathione(GSH)之含量均因預先處理(AC)/sub 5/GP三小時或三天而降低;預先處理(AC)/sub 5/GP三天則造成Glutathione-S-transferase之活性下降,顯示以(AC)/sub 5/GP之處理對於AFB/sub 1/造成之急性肝毒性並沒有抑制現象,反而有增強之效應。 而以(AC)/sub 5/GP預先處理三天,再同時處理AFB/sub 1/(每星期5次,共8星期)之後,則發現由AFB/sub 1/所引起老鼠肝臟中.gamma.-GTase larger foci可被抑制為.gamma.-GTase smaller foci,表示老鼠受AFB/sub 1/長期注射處理之後在Liver carcinoma promotion階段可被(AC)/sub 5/GP所抑制。
Penta-acetyl geniposide ((AC)/sub 5/GP) has potention effect on the acute rat liver carcinogenesis-induced by AFB/sub 1/; but it can suppress the rat liver chronic carcinogenesis-induced by AFB/sub 1/. After gastric intubation for (AC)/sub 5/GP either 3 days of 3 hr, the rats were i.p. administration for AFB/sub 1/, 24 hr later the sacrificed rats were found liver cytotoxicity increasing extensively than the AFB/sub 1/ control group. And the serum enzymes: Alanine aminotransferase (ALT), Asparate aminotransferase (AST), .gamma.-glutamyl transpeptidase (.gamma.-GTase) activities were remarkably increasing. Either the groups pretreating (AC)/sub 5/GP 3 days or 3 hr then i.p. AFB/sub 1/, the Glutathione (GSH) concentrations in the livers were reduced, and the Glutathione-S-transferase activity were not increased to enhance the detoxication pathway. It means that pretreating (AC)/sub 5/GP 3 days or 3 hr cannot suppress the acute liver toxicity-induced by AFB/sub 1/, but enhance the toxicity. On the chronic i.p. administration of AFB/sub 1/ 8 weeks (5 days/week), (AC)/sub 5/GP pretreating 3 days then gastric intubation for 8 weeks (5 days/week) can suppress the formation of .gamma.-GTase larger foci induced by AFB/sub 1/. (AC)/sub 5/GP seems to suppress liver carcinogenesis on the liver carcinoma promotion stage-induced by AFB/sub 1/. |
