Belai A, Wheeler H, Burnstock G
Department of Anatomy and Developmental Biology, University College London, U.K.
Int J Dev Neurosci. 1995 Apr;13(2):81-95. doi: 10.1016/0736-5748(95)00005-2.
The effect of age on the adrenergic and peptidergic innervation of the lower oesophageal, pyloric and ileocaecal sphincters of the rat was investigated using immunohistochemical techniques. The distribution of nerve fibres containing the neuronal protein, growth associated protein-43, was also studied to determine the integrity of the enteric nervous system during development and aging. The four age groups examined were 2-3 days, 6 weeks, 3 months and 25 months old rats. Using protein gene product 9.5 antibody (a non-specific general neuronal marker), it was revealed that the myenteric ganglia in all sphincter regions were compactly arranged and were smaller in size at neonatal stage getting more spaced out and larger in size with age. There was no obvious change in the structure of the neutral elements with age. In the lower oesophageal sphincter, calcitonin gene-related peptide- and substance P-like immunoreactive nerve fibres showed notable changes in density and fluorescence intensity with age, decreasing and increasing, respectively, with no obvious change in vasoactive intestinal polypeptide- and growth-associated protein-like immunoreactivity. A slight increase in dopamine-beta-hydroxylase-like immunoreactivity was seen in old age. In the pyloric sphincter, there was an increase in calcitonin gene-related peptide- and substance P-like immunoreactivity with a less notable increase in dopamine-beta-hydroxylase-like immunoreactivity. A decrease in vasoactive intestinal polypeptide- and growth-associated protein-43-like immunoreactivity in the circular muscle of the sphincter was seen in old age. In the ileocaecal sphincter there was a marked increase in growth associated protein-43-, vasoactive intestinal polypeptide-, dopamine-beta-hydroxylase and substance P-like immunoreactivity. There was a decrease in the density of calcitonin gene-related peptide-like immuno-reactive nerve fibres in old age. In summary, two main conclusions can be drawn from the results of the present study. First, there was an age-related differential change in the density of immunoreactive nerve fibres containing various neuroactive substances. This indicates a level of plasticity of the various enteric nerve types and may reflect the degree of importance of the different neurotrasmitters in the physiological activities of the specific sphincter.(ABSTRACT TRUNCATED AT 400 WORDS)
采用免疫组织化学技术研究了年龄对大鼠食管下括约肌、幽门括约肌和回盲括约肌肾上腺素能和肽能神经支配的影响。还研究了含有神经元蛋白生长相关蛋白-43的神经纤维的分布，以确定发育和衰老过程中肠神经系统的完整性。所检查的四个年龄组分别为2 - 3日龄、6周龄、3月龄和25月龄的大鼠。使用蛋白基因产物9.5抗体（一种非特异性的一般神经元标记物），发现所有括约肌区域的肌间神经节排列紧密，在新生阶段体积较小，随着年龄增长间距增大且体积变大。神经元件的结构随年龄没有明显变化。在食管下括约肌，降钙素基因相关肽和P物质样免疫反应性神经纤维的密度和荧光强度随年龄有显著变化，分别降低和增加，而血管活性肠肽和生长相关蛋白样免疫反应性无明显变化。老年时多巴胺-β-羟化酶样免疫反应性略有增加。在幽门括约肌，降钙素基因相关肽和P物质样免疫反应性增加，多巴胺-β-羟化酶样免疫反应性增加不太明显。老年时括约肌环行肌中血管活性肠肽和生长相关蛋白-43样免疫反应性降低。在回盲括约肌，生长相关蛋白-43、血管活性肠肽、多巴胺-β-羟化酶和P物质样免疫反应性显著增加。老年时降钙素基因相关肽样免疫反应性神经纤维密度降低。总之，从本研究结果可以得出两个主要结论。第一，含有各种神经活性物质的免疫反应性神经纤维密度存在与年龄相关的差异变化。这表明各种肠神经类型具有一定程度的可塑性，可能反映了不同神经递质在特定括约肌生理活动中的重要程度。（摘要截短至400字）
