Shamberger R J
Biochem J. 1969 Feb;111(3):375-83. doi: 10.1042/bj1110375.
Rat mammary tumours induced by 7,12-dimethylbenz[a]anthracene can undergo repeated growth and regression during successive pregnancies. In a 10-day period after birth about half of the tumours regressed 50% or more. The concentrations of the lysosomal enzymes increased in regressing mammary tumours to the following multiples of the initial values: beta-glucuronidase, 7.7; beta-galactosidase, 3.9; cathepsin, 2.9; acid ribonuclease, 2.1; arylsulphatase A, 1.5; acid phosphatase, 1.4. In contrast, several non-lysosomal enzymes failed to increase. Activities in the post-partum uterus increased to the following multiples of the initial values: beta-glucuronidase, 5.8; cathepsin, 5.5; acid ribonuclease, 4.3; beta-galactosidase, 2.2; acid phosphatase, 1.8. Arylsulphatase A in the post-partum uterus decreased significantly, suggesting a non-lysosomal distribution or a special function related to pregnancy. No other significant changes were observed in the lysosomal or non-lysosomal enzymes in the hormone-independent liver or hormone-dependent normal mammary gland. The ratio of free to bound arylsulphatase A and acid ribonuclease decreased slightly 1-3 days after birth because of problems in homogenizing the tumours. At days 4-8, however, there was a dramatic increase in the ratio of the free to bound activities. The results can be explained in terms of the lysosomal theory of intracellular digestion.
由7,12-二甲基苯并[a]蒽诱导产生的大鼠乳腺肿瘤在连续妊娠期间会经历反复的生长和消退。在出生后的10天内，约一半的肿瘤消退了50%或更多。溶酶体酶的浓度在消退的乳腺肿瘤中增加至初始值的以下倍数：β-葡萄糖醛酸酶，7.7；β-半乳糖苷酶，3.9；组织蛋白酶，2.9；酸性核糖核酸酶，2.1；芳基硫酸酯酶A，1.5；酸性磷酸酶，1.4。相比之下，几种非溶酶体酶并未增加。产后子宫中的活性增加至初始值的以下倍数：β-葡萄糖醛酸酶，5.8；组织蛋白酶，5.5；酸性核糖核酸酶，4.3；β-半乳糖苷酶，2.2；酸性磷酸酶，1.8。产后子宫中的芳基硫酸酯酶A显著降低，表明其分布非溶酶体性或与妊娠相关的特殊功能。在激素非依赖性肝脏或激素依赖性正常乳腺中，未观察到溶酶体或非溶酶体酶有其他显著变化。由于肿瘤匀浆存在问题，出生后1 - 3天，游离型与结合型芳基硫酸酯酶A和酸性核糖核酸酶的比例略有下降。然而，在第4 - 8天，游离型与结合型活性的比例急剧增加。这些结果可以根据细胞内消化的溶酶体理论来解释。
