Evidence for a neuromuscular mechanism involved in the contractility of the ovarian follicular wall: fluorescence and electron microscopy and effects of tyramine on follicle strips.
Evidence for a neuromuscular mechanism involved in the contractility of the ovarian follicular wall: fluorescence and electron microscopy and effects of tyramine on follicle strips.
复制标题
涉及卵巢卵泡壁收缩性的神经肌肉机制的证据：荧光和电子显微镜以及酪胺对卵泡条的影响。
作者：
B. Walles;L. Edvinsson;B. Falck;C. Owman;N. Sjöberg;K. Svensson
用荧光组织化学（甲醛法）和电镜相结合的方法，研究了牛Graafian卵泡（直径约10-20 mm）突出部的肾上腺素能神经支配。使用酪胺在体外测试来自卵泡壁的条带的机械响应，酪胺是通过释放内源性神经去甲肾上腺素起作用的间接拟交感神经剂。获得了如下结果：I.甲酰胺诱导的去甲肾上腺素的荧光特性被证明在许多肾上腺素能神经末梢，血管以及非血管，在卵泡壁。2.戊二醛-锇固定组织的电子显微镜显示存在非血管平滑肌样细胞，其特征为肌纤维、致密体和微胞饮小泡，在外膜内成组排列。细胞彼此紧密相关（相邻细胞之间仅约30-100 nm的距离）并且具有基本上平行于表面的方向。3.电子显微镜还显示成束的无髓鞘神经在基质中发出分支，在平滑肌样细胞之间以及肌肉血管。靠近平滑肌样细胞的神经末梢部分缺乏雪旺细胞鞘，并达到接近50 nm的细胞膜。4.关于轴突静脉曲张中突触囊泡（直径30-70 nm）的出现，有理由假设平滑肌样细胞的神经既属于肾上腺素能神经又属于胆碱能神经。5.酪胺产生了剂量依赖性的收缩，从卵泡壁的孤立条。先前暴露于去甲肾上腺素可增强该作用，可卡因可抑制该作用，可卡因可阻断神经对添加的去甲肾上腺素的摄取。这证实了肾上腺素能神经的存在，它可以释放去甲肾上腺素，使卵泡壁收缩。
The adrenergic innervation in the protruding part of the bovine Graafian follicle (about 10-20 mm in diameter) was studied by a combination of fluorescence histochemistry (formaldehyde technique) and electron microscopy. The mechanical response of strips from the follicle wall was tested in vitro using tyramine, which is an indirect sympathomimetic agent acting by releasing endogenous neural norepinephrine. The following results were obtained: I. A formaldehyde-induced fluorescence characteristic of norepinephrine was demonstrated in numerous adrenergic nerve terminals, vascular as well as non-vascular, in the follicle wall. 2. Electron microscopy of glutaraldehyde-osmium-fixed tissue showed the presence of non-vascular smooth muscle-like cells-characterized by myofllaments, dense bodies and micropinocytotic vesicles -arranged in groups within the theca externa. The cells were closely related to each other (only about 30-100 nm distance between adjacent cells) and had a direction essentially parallel to the surface. 3. Electron microscopy also revealed bundles of non-myelinated nerves in the stroma issuing branches in among the smooth muscle-like cells as well as to muscular blood vessels. Close to the smooth muscle-like cells the nerve terminals were partly devoid of Schwann cell ensheathing and reached as close as 50 nm to the membrane of the cells. 4. With regard to the appearance of the synaptic vesicles (30-70 nm in diameter) in the axon varicosities there is reason to assume that the nerves to the smooth muscle-like cells are both of adrenergic and cholinergic type. 5. Tyramine produced a dose-dependent contraction of isolated strips from the follicle wall. The effect was potentiated by previous exposure to norepinephrine and this potentiation was inhibited by cocaine which blocks the uptake of added norepinephrine into the nerves. This confirms the presence of adrenergic nerves which can release norepinephrine to produce a contraction in the follicle wall.