Hourdry Jacques
Laboratoire de Biologie-Vertébrés, Université Paris XI, Centre d'Orsay, 91405, Orsay, France.
Wilhelm Roux Arch Entwickl Mech Org. 1974 Sep;174(3):222-233. doi: 10.1007/BF00573226.
The whole specific activities of 5 lysosomal enzymes (acid phosphatase, N-acetylβ-glucosaminidase,β-glucuronidase, cathepsin and aryl sulphatase) were measured in the guts of Discoglossus tadpoles, before and during metamorphosis.For each hydrolase, the activities show the same variation pattern. They significantly increase at the end of prometamorphosis and the beginning of the climax, while there is histolysis of the first (primary) epithelium of the gut.The measured activities decrease at the end of the climax, while a secondary, enzyme-negative epithelium is developing.The free specific activity of the acid phosphatase was measured in these same guts. It significantly increases at the end of prometamorphosis and the beginning of the climax, during the epithelial histolysis. The total activity increases more slowly than the free one.In the same way, an increase is obtained for the specific activity of the bound (intralysosomal) acid phosphatase.The changes in whole enzymatic activities may result from accelerated synthesis of lysosomal hydrolases due to the primary epitheliocytes, and induced by the simultaneous increase in the plasmatic level of the thyroid hormones. Furthermore the free activity of the acid phosphatase may produce an increased permeability or a breaking of the lysosomal membrane, by the same hormones.
在盘舌蟾蝌蚪变态前和变态期间，测定了其肠道中5种溶酶体酶（酸性磷酸酶、N - 乙酰β - 氨基葡萄糖苷酶、β - 葡萄糖醛酸酶、组织蛋白酶和芳基硫酸酯酶）的总比活性。对于每种水解酶，活性呈现相同的变化模式。在变态前末期和高潮期开始时，它们显著增加，此时肠道的第一层（初级）上皮发生组织溶解。在高潮期末期，测定的活性下降，同时一种次级的、酶阴性上皮正在发育。在相同的这些肠道中测定了酸性磷酸酶的游离比活性。在变态前末期和高潮期开始时，在上皮组织溶解过程中，其显著增加。总活性的增加比游离活性的增加更为缓慢。同样，结合型（溶酶体内）酸性磷酸酶的比活性也有所增加。整个酶活性的变化可能是由于初级上皮细胞导致溶酶体水解酶的合成加速，并由甲状腺激素血浆水平的同时升高所诱导。此外，酸性磷酸酶的游离活性可能由相同的激素导致溶酶体膜通透性增加或破裂。
