ADRENALECTOMY OR SUPERIOR CERVICAL GANGLIONECTOMY MODIFIES THE NOCTURNAL INCREASE IN RAT PINEAL TYPE-II THYROXINE 5'-DEIODINASE
ADRENALECTOMY OR SUPERIOR CERVICAL GANGLIONECTOMY MODIFIES THE NOCTURNAL INCREASE IN RAT PINEAL TYPE-II THYROXINE 5'-DEIODINASE
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DOI：
10.3109/07420529309059696
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发表时间：
1993-04-01
影响因子：
2.8
通讯作者：
GUERRERO, JM
中科院分区：
文献类型：
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作者：
JIMENEZ, J;OSUNA, C;GUERRERO, JM
本文研究了大鼠松果体和其它组织中Ⅱ型甲状腺素5 '-脱碘酶（5'-D）活性对上级颈神经节切除术（SCGX）和肾上腺切除术（ADX）的反应。结果表明，在白天，对照组和SCGX组动物之间没有发现差异，但在夜间，SCGX改变了松果体中5 '-D活性的昼夜周期。以同样的方式，ADX没有改变白天在松果体，哈氏腺，垂体，或大脑额叶皮层（BFC）的酶活性。然而，在棕色脂肪组织（BAT）中，甲状腺激素代谢极其依赖于血液循环中的儿茶酚胺对α 1-肾上腺素能刺激，5 '-D活性显著降低。在对照组中松果体5 '-D活性最大的时间点（02：00 h），ADX动物没有表现出与对照大鼠发生的酶活性的夜间增加。此外，在04：00 h，ADX对松果体5 '-D活性没有任何影响。这些结果似乎表明，血液中的儿茶酚胺的存在是必要的松果体5 '-D活性夜间增加，虽然它不参与调节白天的基础酶活性。
We studied the response of type II thyroxine 5'-deiodinase (5'-D) activity to superior cervical ganglionectomy (SCGX) or adrenalectomy (ADX) in the rat pineal gland and other tissues. The results show that no difference was found between controls and SCGX animals during the day, but at night, SCGX modified the day-night cycle of 5'-D activity in the pineal gland. In the same way, ADX did not modify the enzyme activity during the day in pineal gland, harderian gland, hypophysis, or brain frontal cortex (BFC). However, in brown adipose tissue (BAT), where thyroid hormone metabolism is extremely dependent on alpha1-adrenergic stimulation by blood circulating catecholamines, 5'-D activity is significantly decreased. At the time point of maximal pineal 5'-D activity in controls (02:00 h), ADX animals did not exhibit the nocturnal increase of the enzyme activity that occurs with control rats. Moreover, at 04:00 h ADX did not show any effect on pineal 5'-D activity. These results seem to suggest that the presence of catecholamines in blood is necessary for the pineal 5'-D activity nocturnal increase, although it does not participate in regulating the basal enzyme activity during the day.