P物质在大鼠脑室管膜中定位分布的免疫组织化学研究

A HISTOCHEMICAL STUDY OF LOCALIZATION OF SUBSTANCE P IN THE EPENDYMA OF THE RAT

Immunohistochemical ABC technique was applied to study whether and how the neuropeptide,substance P(SP)existed in the ependyma of the rat.The results showed that there were some ependymocytes which were positive by SP immunoreactive in the wall of the third ventricle(V3),the aqueduct of midbrain(MA)and the central canal(CC)of medulla oblongata. These cells belonged to tanycytes and situated only in the ependyma of V3(hypothalamic tuberal area)and CC of medulla oblongata(area postrema),the former tanycytes were ovoid or pyramid with short basal processes into the subependyma,the latter situated more in the dorsal part of CC with cuboid shape and less in lateral and ventral parts of CC with ovoid shape. Their long basal processes extended into the central gray of medulla oblongata which were near the nucleus of the solitary tract,dorsal moter nucleus of vagus,and the hypoglossal nucleus. Since hypothalamus and area postrema are important centers in regulating the motions of internal organs,endocrine and emotions,our results have afforded a new direct evidence which suggests that tanycytes with some neuropeptides may be a new way to communicate the neuroregulation with the humoral regulation,which may be important in physiology.There are many questions on tanycytes remain further studied.