Pino R, Failli P, Mazzetti L, Buffoni F
Department of Pharmacology, University of Florence, Italy.
Biochem Mol Med. 1997 Dec;62(2):188-96. doi: 10.1006/bmme.1997.2633.
In the isolated cardiomyocytes of spontaneously hypertensive rats (SHR, 3 months old) MAO A and B activities were significantly increased compared to the myocytes in the hearts of age-matched Wistar-Kyoto rats. This increase was not associated with cardiac hypertrophy in these young animals, but might represent an early event in the development of hypertrophy. A semicarbazide-sensitive amine oxidase (SSAO) activity was found in cardiomyocytes. This activity showed a high affinity for benzylamine (Km 5-6 microM) and was not inhibited by 10(-4) M pargyline and 10(-5) M deprenyl, but was largely inhibited by 10(-4) M B24 (3,5-diethoxy-4-aminomethylpyridine), a specific inhibitor of semicarbazide-sensitive amino oxidase with high affinity for benzylamine. The SSAO enzyme of rat cardiomyocytes is a copper-amine oxidase and has a crossreactivity with the antibodies raised against pure pig plasma benzylamine oxidase. In the cardiomyocytes of 3-month old SHR rats the level of this enzymic activity is not significantly increased.
与年龄匹配的Wistar-Kyoto大鼠心脏中的心肌细胞相比，自发性高血压大鼠（SHR，3月龄）分离的心肌细胞中MAO A和B的活性显著增加。这种增加与这些幼年动物的心脏肥大无关，但可能是肥大发展过程中的早期事件。在心肌细胞中发现了一种氨基脲敏感胺氧化酶（SSAO）活性。该活性对苄胺具有高亲和力（Km 5-6 microM），不受10(-4) M帕吉林和10(-5) M司来吉兰抑制，但在很大程度上受10(-4) M B24（3,5-二乙氧基-4-氨基甲基吡啶）抑制，B24是一种对苄胺具有高亲和力的氨基脲敏感氨基氧化酶的特异性抑制剂。大鼠心肌细胞的SSAO酶是一种铜胺氧化酶，与针对纯猪血浆苄胺氧化酶产生的抗体具有交叉反应性。在3月龄SHR大鼠的心肌细胞中，这种酶活性水平没有显著增加。
