Arciszewski M B, Całka J, Wasowicz K, Majewski M
Department of Animal Anatomy and Histology, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033, Lublin, Poland.
Pol J Vet Sci. 2009;12(4):423-31.
Recent decades has brought significant advances in our knowledge of the chemical coding and function of enteric neurons. Calcium ions are important second messenger involved in many aspects of neuron physiology. In the present study, we analyzed immunohistochemically the presence of calcium binding proteins (calretinin and calbindin) in various subpopulations of enteric neurons from the ovine duodenum. Ten percent of submucous neurons were immunoreactive (IR) to calretinin. The presence of calretinin was not detected in myenteric neurons. Calretinin-expressing nerve fibres were found in both myenteric and submucous ganglia, between the circular and longitudinal smooth muscle layers and in the lamina muscularis mucosae. Calretinin-IR submucous neurons did not exhibit the presence of SP, NPY and VIP. Co-localization of calretinin and serotonin was found only in a small number of submucous neurons. Calbindin was expressed in 35% of myenteric neurons and in 60% of submucous neurons. Nerve fibres containing calbindin were localized in myenteric and submucous ganglia where they frequently formed basket-like formations. Calbindin-positive nerve fibres emerging from myenteric ganglia ran between the circular and longitudinal smooth muscle layers. Immunoreactivity to calbindin was also visualized in the lamina muscularis mucosae, around mucosal glands and blood vessels. None of calbindin-IR myenteric neurons revealed immunoreactivity to SP, NPY, VIP and serotonin. Virtually all calbindin-expressing submucous neurons were SP-positive. In moderate numbers of submucous perikarya, co-incidence of calbindin and NPY, calbindin and VIP or calbindin and serotonin was observed. We conclude that in the ovine duodenum, the expression of calretinin and calbindin is species specific. Co-localization studies and distribution patterns indicate that in the duodenum of the sheep, calretinin and calbindin may be present in several functional subclasses of enteric neurons.
近几十年来，我们对肠神经元的化学编码和功能的认识取得了重大进展。钙离子是参与神经元生理学许多方面的重要第二信使。在本研究中，我们采用免疫组织化学方法分析了绵羊十二指肠肠神经元各亚群中钙结合蛋白（钙视网膜蛋白和钙结合蛋白）的存在情况。10%的黏膜下神经元对钙视网膜蛋白呈免疫反应性（IR）。在肌间神经元中未检测到钙视网膜蛋白的存在。在肌间和黏膜下神经节、环形和纵行平滑肌层之间以及黏膜肌层中发现了表达钙视网膜蛋白的神经纤维。钙视网膜蛋白免疫反应性黏膜下神经元未显示P物质（SP）、神经肽Y（NPY）和血管活性肠肽（VIP）的存在。仅在少数黏膜下神经元中发现了钙视网膜蛋白和5-羟色胺的共定位。35%的肌间神经元和60%的黏膜下神经元表达钙结合蛋白。含有钙结合蛋白的神经纤维位于肌间和黏膜下神经节，在那里它们经常形成篮状结构。从肌间神经节发出的钙结合蛋白阳性神经纤维在环形和纵行平滑肌层之间穿行。在黏膜肌层、黏膜腺和血管周围也可见到对钙结合蛋白的免疫反应性。钙结合蛋白免疫反应性肌间神经元对SP、NPY、VIP和5-羟色胺均无免疫反应性。几乎所有表达钙结合蛋白的黏膜下神经元均为SP阳性。在中等数量的黏膜下核周体中，观察到钙结合蛋白与NPY、钙结合蛋白与VIP或钙结合蛋白与5-羟色胺的共定位。我们得出结论，在绵羊十二指肠中，钙视网膜蛋白和钙结合蛋白的表达具有物种特异性。共定位研究和分布模式表明，在绵羊十二指肠中，钙视网膜蛋白和钙结合蛋白可能存在于肠神经元的几个功能亚类中。
