Neuronal properties in cultured ultimobranchial C cells of chick embryos: process outgrowth and expression of TuJ1 and enkephalin.
We have analyzed the neuronal properties in cultured ultimobranchial C cells isolated from embryonic chicks at different developmental stages (12--16 days of incubation) by immunohistochemistry and electron microscopy. The ultimobranchial glands mostly consist of C cell solids. In 13-day-old embryos, many C cells cultured for 7 days on laminin-coated slides extended long neurite-like processes, reaching 300 microm in length. Neuritic outgrowth of C cells was regulated developmentally and virtually unaffected by nerve growth factor (NGF). The cultured C cells expressed intense immunoreactivity for calcitonin and enkephalin. It was also confirmed by confocal laser-scanning microscopy that almost all C cells were intensely immunostained by both the calcitonin antiserum and the monoclonal antibody TuJ1, a neuron-specific marker. Scanning electron microscopy identified the outgrowth of long, branching neuritic processes emerging from C cell soma. The processes had numerous varicosities along their course and ended in growth cones. The C cells with processes were usually monopolar and less frequently bipolar or multipolar. Transmission electron microscopy revealed the presence of membrane-bounded secretory granules in the cultured C cells. The neuritic processes of C cells contained aggregations of microfilaments, intermediate filaments and microtubules arranged in parallel to the long axis. In addition, synaptic-like contacts showing desmosome-like membrane-thickenings and accumulations of small clear vesicles and dense-cored vesicles were formed between the endings of the processes and the surface of C cells. These results indicate that the C cells cultured from early chick embryos (12- and 13-day-old) maintain the neuronal characteristics for long periods in vitro.
Miura
M
M
Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 228, Japan.
Kameda
Y
Y
D000818:Animals; D002116:Calcitonin / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D048429:Cell Size / Q000502:physiology; D002478:Cells, Cultured / Q000378:metabolism / Q000648:ultrastructure; D002642:Chick Embryo / Q000196:embryology* / Q000378:metabolism / Q000648:ultrastructure; D004745:Enkephalins / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000493:pharmacokinetics; D020439:Growth Cones / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008870:Microtubules / Q000378:metabolism / Q000648:ultrastructure; D016501:Neurites / Q000378:metabolism* / Q000648:ultrastructure; D022142:Secretory Vesicles / Q000378:metabolism / Q000648:ultrastructure; D013234:Stem Cells / Q000378:metabolism / Q000648:ultrastructure; D014404:Tubulin / Q000276:immunology / Q000378:metabolism*; D014460:Ultimobranchial Body / Q000166:cytology / Q000196:embryology* / Q000378:metabolism
D004745:Enkephalins; D005456:Fluorescent Dyes; D014404:Tubulin; D002116:Calcitonin