Department of Pharmaceutical Sciences, Nagpur University Campus, Nagpur 440 010, India.
J Chem Neuroanat. 2011 Mar;41(2):122-8. doi: 10.1016/j.jchemneu.2010.12.004. Epub 2010 Dec 22.
The subcommissural organ (SCO) is a highly specialised circumventricular ependymal organ covering and penetrating the posterior commissure. The secretory products of the SCO condense to form Reissner's fiber (RF). Because of its extensive secretory activity and the chemical properties of its secretion, the organ functions as similar to the neurosecretory cells. Teleosts comprised of more than 20,000 extant species that show great diversity in terms of the form, habit and habitat. Affinity of calcitonin antibodies for the SCO-RF complex was used as a histochemical tool to study the morphology of some freshwater and seawater teleosts and its potential correlate to their osmotic environment. While intense to moderate calcitonin-like immunoreactivity was seen in the cells of the SCO of majority of the freshwater species viz., common carp, catfish, eel and perch; the SCO of goldfish revealed limited immunoreactivity. Like the SCO, the RF in all species was also immunostained with antibodies against calcitonin. It appeared as a single, continuous fiber that ran from SCO into the third ventricle and extended through the aqueduct, fourth ventricle and central canal of the spinal cord. In contrast to that in the freshwater fishes, the SCO-RF complex in majority of the seawater fishes, showed no calcitonin-like immunoreactivity. The data presented in this study described the comparative histomorphology of the SCO-RF complex and suggest a possibility that the calcitonin-like immunoreactivity in the SCO-RF complex might be a feature correlated to the osmotic environment of the fish.
室下器官（SCO）是一种高度特化的室管膜下器官，覆盖并穿透后连合。SCO 的分泌产物凝结形成 Reissner 纤维（RF）。由于其广泛的分泌活动和分泌产物的化学性质，该器官的功能类似于神经分泌细胞。硬骨鱼类由超过 20,000 种现存物种组成，在形态、习性和栖息地方面表现出极大的多样性。降钙素抗体与 SCO-RF 复合物的亲和力被用作研究一些淡水和海水硬骨鱼类形态的组织化学工具，并研究其与渗透环境的潜在相关性。虽然在大多数淡水物种（如鲤鱼、鲶鱼、鳗鱼和鲈鱼）的 SCO 细胞中观察到强烈到中度的降钙素样免疫反应，但金鱼的 SCO 显示出有限的免疫反应。与 SCO 一样，所有物种的 RF 也被针对降钙素的抗体免疫染色。它呈现为一条单一的、连续的纤维，从 SCO 延伸到第三脑室，并通过导水管、第四脑室和脊髓中央管延伸。与淡水鱼类不同的是，大多数海水鱼类的 SCO-RF 复合物没有降钙素样免疫反应。本研究提供的资料描述了 SCO-RF 复合物的比较组织形态学，并提出了这样一种可能性，即 SCO-RF 复合物中的降钙素样免疫反应可能是与鱼类渗透环境相关的特征。
