Loesch A, Burnstock G
Department of Anatomy and Developmental Biology, University College London, UK.
J Neurocytol. 1996 Sep;25(9):525-34. doi: 10.1007/BF02284820.
The ultrastructural distribution of neuronal (type I) and endothelial (type III) isoforms of nitric oxide synthase in perivascular axons and endothelial cells was examined in the Wistar rat cerebral basilar artery, employing monoclonal antibodies specific either to type I or type III of nitric oxide synthase in pre-embedding peroxidase-antiperoxidase immunocytochemistry. Both neuronal and endothelial nitric oxide synthase were localized in similar proportions of perivascular axons (25.2% +/- 2.8 and 28.7% +/- 6.5, respectively) but in different proportions in vascular endothelial cells (6.2% +/- 0.9 and 27.1% +/- 2.4, respectively). The intracellular distribution of immunoreactivity to neuronal and endothelial nitric oxide synthase was similar both in axons and endothelial cells; e.g. the labelling of the membranes of mitochondria and synaptic/cytoplasmic vesicles. However, the intensity of immunoreactivity was most prominent in profiles positive for endothelial nitric oxide synthase. The neuronal and endothelial nitric oxide synthase-positive axon varicosities were characterized by the presence of small spherical agranular vesicles; agranular vesicles in nerve varicosities positive for neuronal nitric oxide synthase were significantly larger than those in nerve varicosities positive for endothelial nitric oxide synthase (43.2 nm +/- 0.5 versus 37.7 nm +/- 0.8; p < 0.001). Varicosities positive for endothelial nitric oxide synthase also contained large granular vesicles (116.6 nm +/- 5.9) with labelled cores. In conclusion, the present data demonstrate that monoclonal antibodies to neuronal and endothelial nitric oxide synthase immunoreact with subpopulations of both perivascular axons and endothelial cells of rat basilar artery. The significance of neuronal and endothelial isoforms of nitric oxide synthase for the basilar artery is discussed.
采用包埋前过氧化物酶-抗过氧化物酶免疫细胞化学方法，使用对一氧化氮合酶I型或III型特异的单克隆抗体，在Wistar大鼠脑基底动脉中检测了血管周围轴突和内皮细胞中神经元型（I型）和内皮型（III型）一氧化氮合酶的超微结构分布。神经元型和内皮型一氧化氮合酶在相似比例的血管周围轴突中定位（分别为25.2%±2.8和28.7%±6.5），但在血管内皮细胞中的比例不同（分别为6.2%±0.9和27.1%±2.4）。在轴突和内皮细胞中，神经元型和内皮型一氧化氮合酶免疫反应性的细胞内分布相似；例如，线粒体膜和突触/细胞质囊泡的标记。然而，免疫反应性强度在内皮型一氧化氮合酶阳性的细胞中最为突出。神经元型和内皮型一氧化氮合酶阳性的轴突膨体的特征是存在小的球形无颗粒囊泡；神经元型一氧化氮合酶阳性神经膨体中的无颗粒囊泡明显大于内皮型一氧化氮合酶阳性神经膨体中的无颗粒囊泡（43.2 nm±0.5对37.7 nm±0.8；p<0.001）。内皮型一氧化氮合酶阳性的膨体还含有带标记核心的大颗粒囊泡（116.6 nm±5.9）。总之，目前的数据表明，针对神经元型和内皮型一氧化氮合酶的单克隆抗体与大鼠基底动脉血管周围轴突和内皮细胞的亚群发生免疫反应。讨论了一氧化氮合酶的神经元型和内皮型异构体对基底动脉的意义。
