Thorbert G, Alm P, Björklund A B, Owman C, Sjöberg N O
Am J Obstet Gynecol. 1979 Sep 15;135(2):223-6. doi: 10.1016/0002-9378(79)90348-x.
The uterine adrenergic transmitter is in many animal species dramatically reduced during pregnancy, probably leading to a functional denervation near term. In order to clarify whether similar changes also occur in the human uterus, the adrenergic innervation of the isthmic myometrium during nonpregnant and pregnant conditions was analyzed by fluorescence histochemistry for demonstration of adrenergic nerves, and by quantitative measurements of norepinephrine and its synthesizing enzymes, tyrosine hydroxylase and dopa decarboxylase. At term pregnancy all fluorescent adrenergic nerves in the myometrium had disappeared, and the norepinephrine concentration had been reduced to almost zero. Parallel to this the activities of tyrosine hydroxylase and dopa decarboxylase were markedly reduced. By contrast, the activity of the acetylcholine-synthesizing enzyme, choline acetyltransferase, was unchanged, indicating that the adrenergic system was selectively affected. The results confirm that the adrenergic nerves in the human uterus, like those in uterine horns of laboratory animals, undergo fundamental changes in the course of pregnancy. This probably reflects entirely different conditions for a sympathetic influence on the myometrium during the last two trimesters of pregnancy compared to the non-pregnant situation.
在许多动物物种中，子宫内的肾上腺素能递质在怀孕期间会显著减少，这可能导致临近足月时出现功能性去神经支配。为了阐明人类子宫是否也会发生类似变化，通过荧光组织化学法来显示肾上腺素能神经，并对去甲肾上腺素及其合成酶酪氨酸羟化酶和多巴脱羧酶进行定量测量，分析了非孕期和孕期子宫峡部肌层的肾上腺素能神经支配情况。足月妊娠时，肌层内所有荧光肾上腺素能神经均消失，去甲肾上腺素浓度几乎降至零。与此同时，酪氨酸羟化酶和多巴脱羧酶的活性显著降低。相比之下，乙酰胆碱合成酶胆碱乙酰转移酶的活性未发生变化，这表明肾上腺素能系统受到了选择性影响。结果证实，人类子宫中的肾上腺素能神经与实验动物子宫角中的神经一样，在妊娠过程中会发生根本性变化。这可能反映出在妊娠最后两个阶段，与非妊娠状态相比，交感神经对肌层的影响情况完全不同。
