Hopkins D, Manchester K L
Biochem J. 1981 May 15;196(2):603-10. doi: 10.1042/bj1960603.
Concentrations of spermidine, spermine and putrescine have been measured in rat diaphragm muscle after unilateral nerve section. The concentration of putrescine increased approx. 10-fold 2 days after nerve section, that of spermidine about 3-fold by day 3, whereas an increase in the concentration of spermine was only observed after 7-10 days. It was not possible to show enhanced uptake of either exogenous putrescine or spermidine by the isolated tissue during the hypertrophy. Consistent with the accumulation of putrescine, activity of ornithine decarboxylase increased within 1 day of nerve section, was maximally elevated by the second day and then declined. Synthesis of spermidine from [14C]putrescine and either methionine or S-adenosylmethionine bt diaphragm cytosol rose within 1 day of nerve section, but by day 3 had returned to normal or below normal values. Activity of adenosylmethionine decarboxylase similarly increased within 1 day of nerve section, but by day 3 had declined to below normal values. Activity of methionine adenosyltransferase was elevated throughout the period studied. The concentration of S-adenosylmethionine was likewise enhanced during hypertrophy. Administration of methylglyoxal bis(guanylhydrazone) produced a marked increase in adenosylmethionine decarboxylase activity and a large increase in putrescine concentration, but did not prevent the rise in spermidine concentration produced by denervation. Possible regulatory mechanisms of polyamine metabolism consistent with the observations are discussed.
在大鼠单侧神经切断后的膈膜肌肉中，已对亚精胺、精胺和腐胺的浓度进行了测定。神经切断后2天，腐胺浓度增加了约10倍，到第3天亚精胺浓度增加了约3倍，而精胺浓度仅在7 - 10天后才出现增加。在肥大过程中，无法显示分离组织对外源性腐胺或亚精胺的摄取增强。与腐胺的积累一致，鸟氨酸脱羧酶的活性在神经切断后1天内增加，在第2天达到最大升高，然后下降。膈膜细胞溶质从[14C]腐胺与蛋氨酸或S -腺苷甲硫氨酸合成亚精胺在神经切断后1天内增加，但到第3天已恢复到正常或低于正常水平。腺苷甲硫氨酸脱羧酶的活性同样在神经切断后1天内增加，但到第3天已下降到低于正常水平。在整个研究期间，蛋氨酸腺苷转移酶的活性升高。肥大过程中S -腺苷甲硫氨酸的浓度同样升高。给予甲基乙二醛双（脒腙）使腺苷甲硫氨酸脱羧酶活性显著增加，腐胺浓度大幅增加，但并未阻止去神经支配引起的亚精胺浓度升高。讨论了与这些观察结果一致的多胺代谢可能的调节机制。
