A comparative study of the differentiation of dissociated nerve cells under different culture conditions.

In vitro differentiation of chick embryo brain cells was compared under several culture conditions. Morphological observations and acetylcholinesterase histochemical staining revealed that the development was similar in all conditions tested if cells have been derived from 7 days embryos. Considering the cultures from 11 days embryos, the cell dissociation by trypsin and the plastic surface proved to be the most favourable conditions in contrast to mechanical dissection and collagen surface.     

Histochemical study of dissociated nerve cells from embryonic chick cerebral hemispheres in flask cultures

Zusammenfassung Die Differenzierung von dissoziierten Grosshirnneuronen in Plastikflaschenkulturen wurde mit histochemischen Methoden, Nisslfärbung, Silberimprägnation der Nervenfasern und Acetylcholinesteraseaktivität untersucht.

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with the technical assistance ofM. F. Knoetgen

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Chargée de Recherche au C.N.R.S.     

Simplifications to substrate preparation for the cultivation of dissociated nerve cells

Résumé Nous avons simplifié la méthode de préparation du substrat «collagène» pour la culture de cellules nerveuses dissociées. On obtient une fixation et une différenciation rapide des cellules sur ce substrat. Les cultures conviennent pour des études morphologiques, biochimiques et électrophysiologiques.

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Chargée de Recherche au CNRS.

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Acknowledgments. The technical assistance of Mrs.Dorea van Weele andMrs. Marie-France Knoetgen is gratefully acknowledged.     

A comparative study on the effects of brain extracts and mesodermal membrane extracts on nerve cell differentiation.

Extracts prepared from the mesodermal tissue surrounding the brain stimulate the differentiation of morphologically undifferentiated neuroblasts, while the differentiation of more mature neuroblasts is influenced by brain extracts.     

Comparative morphometric study of the cells of the third proximal segment of the rat kidney under different conditions of fixation.

The morphometric study of the P3 segment of rat proximal tubule has shown that neither the method of fixation, nor the fixative itself, significantly change the relative and absolute volumes of the cell compartments, provided that the fixation media are made approximately isotonic.     

A comparative study of nuclear proteins in chick embryo cells and their primary and secondary fibrobasts in culture

Zusammenfassung Das elektrophoretische Muster von Histonen und sauren Zellkernproteinen von Hühnerembryonen und deren primären und sekundären Fibroblastzellen wurde qualitativ und quantitativ verglichen. Die Zellkernproteine der verschiedenen Zelltypen erwiesen sich qualitativ als identisch, die relative quantitative Verteilung der Kernproteine war jedoch leicht verschieden.     

Autoradiographic study of cartilage differentiation in organ culture

Zusammenfassung Aufnahme und Verhalten von³⁵-S-Sulfat wurde in einer Organkultur sich differenzierender Somiten von Hühner-und Mäuse-Embryonen untersucht. Die Vorknorpelzellen zeigten den grössten Isotopeneinbau im Vergleich zu andern mesodermalen Zellen. Nach Vollendung der Knorpeldifferenzierung fand sich das von den Vorknorpelzellen aufgenommene Isotop in der interzellulären Matrix.

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On leave of absence from the Zoological Institute, Faculty of Science, University of Kyoto (Japan).     

A simplified method of nerve organ culture

Résumé Une méthode simplifiée de culture d'organe nerveux est décrite. Elle réduit le temps consacré à la nourriture et permet un changement rapide du milieu nutritif. Elle convient aux études microscopique (m. à contraste de phase) et elle est relativement peu coûteuse.     

Two different aggregation principles in reaggregation process of dissociated sponge cells (Geodia cydonium)

Zusammenfassung Chemisch dissoziierte Zellen des KieselschwammesGeodia cydonium reaggregieren aufgrund zweier verschiedenr Reaggregationsprinzipien. Der Aggnegationsfaktor, auf den die Primäraggregation zurückgeht, ist membrangebunden und wird durch Proteasen nicht inaktiviert. Der sekundäre Aggregationsfaktor wurde 500fach angereichert. Das Molekulargewicht dieses Aggregationsfaktors beträgt etwa 20000 Daltons; er ist mit einem ringförmigen Makromolekül (2×10⁹ Daltons) assoziiert.

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Acknowledgments. We wish to thank Mrs.V. Pondeljak, Mrs.U. Müller-Berger, Mr. R. Beyer andMr. M. Srecec for their excellent technical assistance. We gratefully acknowledge the advice of dipl. Chem.J. Obermeier for the carbodiimide coupling method. This work is supported by Fonds der Chemischen Industrie and by the Landesversicherungsantalt Rheinland-Pfalz, Speyer/Rh.     

Preferential neurotoxicity of pentobarbital on nerve and glial cells in culture

The effect of pentobarbital was studied in a mixed population of nerve and glial cells dissociated from brains of 7-day chick embryos and maintained in culture. Pentobarbital-Na was added in various concentrations ranging from 5 X 10(-5) M to 1 X 10(-3) M. The neuronal density was monitored by counting the neurons, neuronal identity was established by staining for Nissl Bodies and acetylcholinesterase. Over a culture period of 3 weeks, it was found that the barbiturate exerts a preferential dose-dependent cytotoxic effect on neurons.     

Preferential neurotoxicity of pentobarbital on nerve and glial cells in culture

Summary The effect of pentobarbital was studied in a mixed population of nerve and glial cells dissociated from brains of 7-day chick embryos and maintained in culture. Pentobarbital-Na was added in various concentrations ranging from 5×10^–5 M to 1×10^–3 M. The neuronal density was monitored by counting of neurons, neuronal identity was established by staining for Nissl Bodies and acetylcholinesterase. Over a culture period of 3 weeks, it was found that the barbiturate exerts a preferential dose-dependent cytotoxic effect on neurons.The expert technical assistance of Miss A. Wolf is appreciated. This work was supported by grant 6-74-27, INSERM (Physiologie et Pathologie du Développement Nerveux).