Neuropeptide Y (NPY) is widely distributed in the autonomic nervous system and acts as a neurotransmitter and a trophic factor. However, there is no report concerning the expression of NPY and its receptors in the intestine during postnatal ontogenesis. In the current study, immunohistochemistry and western blot analysis was used to label NPY, Y1R, Y2R and Y5R receptors in the duodenum from rats of different ages (1-, 10-, 20-, 30-, 60-day-old and 2-year-old). The obtained data suggest age-dependent changes of NPY-mediated gut innervation. NPY-immunoreactive (IR) neurons were observed in the myenteric (MP) and submucous (SP) plexus from the moment of birth. In the MP, the percentage of NPY-IR neurons was low and varied from 4.1 ± 0.32 in 1-day-old to 2.9 ± 0.62 in 2-year-old rats. The proportion of NPY-IR myenteric neurons did not change significantly through the senescence (p > .05). In the SP, the proportion of NPY-IR neurons significantly increased in the first month of life from 56.3 ± 2.4% in 1-day-old to 78.1 ± 5.18% in 20-day-old and significantly decreased from 75.6 ± 4.62% in 30-day-old rats to 59.8 ± 4.24% in 2-year-old rats. The expression of NPY in the duodenum did not change significantly during the development by western blot analysis. The expression of Y1R and Y2R was low in newborns and upregulated in the first ten days of life. The expression of Y5R was maximal in newborn pups and significantly decreased in in the first 20 days. Thus, there are some fluctuation of the percentage of NPY-IR neurons accompanies changes in relation of different subtypes of NPY receptors in the small intestine during postnatal ontogenesis.

中文翻译：

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大鼠十二指肠神经肽Y能系统的年龄相关变化

神经肽 Y (NPY) 广泛分布在自主神经系统中，作为神经递质和营养因子。然而，没有关于NPY及其受体在出生后个体发育过程中在肠道中的表达的报道。在目前的研究中，免疫组织化学和蛋白质印迹分析被用于标记不同年龄（1-、10-、20-、30-、60- 日龄和 2 日龄）十二指肠中的 NPY、Y1R、Y2R 和 Y5R 受体。 -岁）。获得的数据表明 NPY 介导的肠道神经支配的年龄依赖性变化。从出生那一刻起，就在肌间质 (MP) 和粘膜下 (SP) 神经丛中观察到 NPY 免疫反应 (IR) 神经元。在 MP 中，NPY-IR 神经元的百分比较低，从 1 日龄大鼠的 4.1 ± 0.32 到 2 岁大鼠的 2.9 ± 0.62。NPY-IR 肌间质神经元的比例在衰老过程中没有显着变化（p > .05）。在SP中，NPY-IR神经元的比例在生命的第一个月从1日龄的56.3±2.4％显着增加到20日龄的78.1±5.18％，并从75.6±4.62％显着下降30 日龄大鼠为 2 岁大鼠的 59.8 ± 4.24%。通过蛋白质印迹分析，NPY在十二指肠中的表达在发育过程中没有显着变化。Y1R 和 Y2R 的表达在新生儿中较低，并在生命的前十天上调。Y5R 的表达在新生幼崽中最大，并在前 20 天显着下降。因此，