Hibasami H, Maekawa S, Murata T, Nakashima K
Department of Biochemistry, Mie University School of Medicine, Japan.
Biochem Pharmacol. 1988 Nov 1;37(21):4117-20. doi: 10.1016/0006-2952(88)90104-9.
The intraperitoneal injection of methylglyoxal bis(cyclohexylamidinohydrazone) (MGBC), an inhibitor of S-adenosylmethionine decarboxylase and spermidine synthase, markedly increased (7-fold of the basal level at 4 hr) ornithine decarboxylase (ODC) activity in normal mouse liver. ODC activity was also increased 2.5-fold over the basal level in mouse lung at 6 hr after the injection. The effect of MGBC on ODC activity occurred in a dose-dependent manner. Measurement of the apparent half-life of ODC induced in the liver and lung by MGBC treatment revealed a clear decrease in the decay rate of the enzyme in both the tissues. Activities of S-adenosylmethionine decarboxylase (AdoMetDC) and spermidine/spermine N1-acetyltransferase (SAT) were not increased by the intraperitoneal injection of MGBC. There was a large rise in putrescine and a fall in spermidine and spermine in the liver and lung except for brain within an 8 hr period in response to MGBC, suggesting that these changes resulted from the stabilization of ODC and inhibitions of AdoMetDC and spermidine synthase.
腹腔注射S-腺苷甲硫氨酸脱羧酶和亚精胺合酶抑制剂双（环己脒腙）甲基乙二醛（MGBC），可使正常小鼠肝脏中的鸟氨酸脱羧酶（ODC）活性显著增加（4小时时为基础水平的7倍）。注射后6小时，小鼠肺中的ODC活性也比基础水平增加了2.5倍。MGBC对ODC活性的影响呈剂量依赖性。对MGBC处理诱导的肝脏和肺中ODC的表观半衰期进行测量，结果显示两个组织中该酶的降解速率明显降低。腹腔注射MGBC并未使S-腺苷甲硫氨酸脱羧酶（AdoMetDC）和亚精胺/精胺N1-乙酰基转移酶（SAT）的活性增加。在8小时内，除大脑外，肝脏和肺中的腐胺大量增加，亚精胺和精胺减少，这表明这些变化是由于ODC的稳定以及AdoMetDC和亚精胺合酶受到抑制所致。
