Murakami T
Department of Anesthesiology, Kyoto Prefectural University of Medicine.
Nihon Naibunpi Gakkai Zasshi. 1994 Oct 20;70(8):967-78. doi: 10.1507/endocrine1927.70.8_967.
Nitric oxide (NO), a simple gas with free radical chemical properties, is synthesized by nitric oxide synthase (NOS) from arginine in neurons and acts as a neurotransmitter in the central and peripheral nervous systems. The immunohistochemical demonstration of NOS-immunoreactivity and its histochemical marker, NADPH-diaphorase activity in many neurons of the hypothalamus, suggest that NO plays a role in controlling the production and/or release of hypothalamic neuroendocrine peptides. In the present study, the expression of NOS in the enkephalin and dynorphin systems of the rat hypothalamus was examined by the combined method of the NADPH-diaphorase histochemistry and the immunocytochemistry of methionine enkephalin (M-Enk) or dynorphin B (Dyn-B). About 6 to 9% of M-Enk immunoreactive neurons in the paraventricular, arcuate and ventromedial nuclei expressed NADPH-diaphorase activity. Dyn-B immunoreactive neurons, however, showed NADPH-diaphorase activity in high ratio (37%-84%) in the supraoptic nucleus and the parvocellular and magnocellular paraventricular nucleus. These results revealed that a part of the enkephalin and dynorphin neurons in the rat hypothalamus have the ability to produce NO. The high ratio of expression of NO in magnocellular neurosecretory dynorphin containing neurons suggested that NO participates in controlling posterior pituitary hormone secretion together with dynorphin.
一氧化氮（NO）是一种具有自由基化学性质的简单气体，由一氧化氮合酶（NOS）在神经元中从精氨酸合成，并在中枢和外周神经系统中作为神经递质发挥作用。下丘脑许多神经元中NOS免疫反应性及其组织化学标志物NADPH - 黄递酶活性的免疫组织化学显示，NO在控制下丘脑神经内分泌肽的产生和/或释放中起作用。在本研究中，通过NADPH - 黄递酶组织化学与甲硫氨酸脑啡肽（M - Enk）或强啡肽B（Dyn - B）免疫细胞化学相结合的方法，检测了大鼠下丘脑脑啡肽和强啡肽系统中NOS的表达。室旁核、弓状核和腹内侧核中约6%至9%的M - Enk免疫反应性神经元表达NADPH - 黄递酶活性。然而，Dyn - B免疫反应性神经元在视上核以及室旁核小细胞部和大细胞部中显示出高比例（37% - 84%）的NADPH - 黄递酶活性。这些结果表明，大鼠下丘脑的一部分脑啡肽和强啡肽神经元具有产生NO的能力。含强啡肽的大细胞神经分泌神经元中NO的高表达比例表明，NO与强啡肽一起参与控制垂体后叶激素的分泌。
