Fouchier F, Bastiani P, Dang J
Mol Cell Endocrinol. 1987 Jan;49(1):25-31. doi: 10.1016/0303-7207(87)90060-8.
Pig thyroid slices, pre-labelled with [125I]iodide, were incubated with or without thyrotropin (TSH), dibutyryl cyclic AMP (dbcAMP) or forskolin. After lysosome isolation, intralysosomal thyroglobulin (Tg) hydrolysis was determined by the increment in trichloroacetic acid (TCA)-soluble radioactivity. TSH stimulated the intralysosomal Tg hydrolysis. This stimulation was time and concentration dependent and was mimicked by forskolin or dbcAMP. When endocytosis and protein synthesis were blocked by inhibitors (nocodazole and puromycin) the stimulatory effect was still maintained. We conclude that TSH increases quickly and specifically, via a cAMP-mediated process, intralysosomal Tg hydrolysis, independent of its effects on endocytosis of Tg and lysosomal protease synthesis.
用[125I]碘化物预先标记的猪甲状腺切片，分别在有或无促甲状腺激素（TSH）、二丁酰环磷腺苷（dbcAMP）或福斯可林的情况下进行孵育。分离溶酶体后，通过三氯乙酸（TCA）可溶性放射性的增加来测定溶酶体内甲状腺球蛋白（Tg）的水解情况。TSH刺激溶酶体内Tg的水解。这种刺激具有时间和浓度依赖性，并且可被福斯可林或dbcAMP模拟。当用抑制剂（诺考达唑和嘌呤霉素）阻断内吞作用和蛋白质合成时，刺激作用仍然存在。我们得出结论，TSH通过cAMP介导的过程快速且特异性地增加溶酶体内Tg的水解，而与其对Tg内吞作用和溶酶体蛋白酶合成的影响无关。
