The hypothalamus is the most important integrator of autonomic and endocrine regulation in the body and it also has a fundamental role in ageing development and lifespan control. In order to better understand the role of NO-ergic system in the hypothalamic regulation of ageing, the purpose of this study was to investigate the expression of neuronal nitric oxide synthase (nNOS) in the arcuate (ARC), ventromedial (VMH) and dorsomedial (DMH) hypothalamic nuclei in young (2-3-month-old) and old (24-month-old) male and female rats using immunohistochemistry and western blot analysis. In young animals, only single nNOS-immunoreactive (IR) neurons were detected in ARC, and nNOS-IR neurons were found in the VMH (19 ± 3.2% in females and 14.5 ± 2.6% in males) and DMH (17 ± 4.0% in females and 21 ± 2.8% in males). In aged animals, the number of nNOS-IR neurons increased in all studied nuclei, including ARC (36 ± 3.1% in females and 33.5 ± 3.7% in males), VMH (83 ± 4.3% in females and 58 ± 2.1% in males) and DMH (57 ± 1.9% in females and 54 ± 1.8% in males). The expression of nNOS also significantly increased in the ARC, VMH and DMH during ageing by western blot analysis. In conclusion, ageing is accompanied by increasing of nNOS expression in the hypothalamus and this process is related to regions involved in the control of feeding behavior.

中文翻译：

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衰老过程中丘脑下丘脑核中nNOS表达的变化。

下丘脑是人体自主神经和内分泌调节的最重要整合者，并且在衰老发展和寿命控制中也起着基本作用。为了更好地了解NO能量系统在下丘脑调节衰老中的作用，本研究的目的是研究神经元一氧化氮合酶（nNOS）在弓形（ARC），腹膜（VMH）和背囊中的表达（DMH）下丘脑核在年轻（2-3个月大）和老（24个月大）雄性和雌性大鼠中的免疫组织化学和免疫印迹分析。在幼小动物中，仅在ARC中检测到单个nNOS免疫反应（IR）神经元，而在VMH中发现nNOS-IR神经元（雌性为19±3.2％，雄性为14.5±2.6％）和DMH（17±4.0％女性，男性21±2.8％）。在老年动物中 nNOS-IR神经元的数量在所有研究的核中都增加了，包括ARC（女性为36±3.1％，男性为33.5±3.7％），VMH（女性为83±4.3％，男性为58±2.1％）和DMH（女性为57±1.9％，男性为54±1.8％）。通过蛋白质印迹分析，在老化过程中，ARC，VMH和DMH中nNOS的表达也显着增加。总之，衰老伴随着下丘脑中nNOS表达的增加，并且该过程与控制喂养行为的区域有关。