Demonstration of neuronal activities in primary cultures from fetal mouse hypothalamus maintained in a serum-free medium

Fetal neuronal cells dissociated from mouse hypothalamus are able to grow in a serum-free medium for two to four weeks. Several neuronal activities have been measured during the in vitro cell development. Whereas glutamic acid decarboxylase (EC 4.1.1.15) activity disappears, those of thyroliberin (TRH) and tyrosine hydroxylase (EC. 1.14.16.2) remain stable, and acetylcholine transferase one (EC 2.3.1.6) rises earlier than in a serum supplemented medium. These results show that primary cultures grown in serum-free medium offer a promising model for studying neuronal activity differentiation.     

Studies of the mechanism of action of the carotenoid crocetin.

The carotenoid crocetin was found to be taken up by normal rat muscle cells grown in vitro, and was found in the ribosomal-microsomal fraction, supporting the hypothesis that crocetin affects cell division enzymatic processes.     

Studies of the mechanism of action of the carotenoid crocetin

Summary The carotenoid crocetin was found to be taken up by normal rat muscle cells grown in vitro, and was found in the ribosomal-microsomal fraction, supporting the hypothesis that crocetin affects cell division enzymatic processes.     

Preimplantation mouse embryos cultured in mouse, rat and human sera: differentiation and sister chromatid exchange

Development of 4-cell and of 8-cell mouse embryos and of morulae and blastocysts is inhibited in vitro by mouse serum but not by rat or human sera which also do not influence sister chromatid exchange in cultured morulae and blastocysts.     

Preimplantation mouse embryos cultured in mouse,rat and human sera: differentiation and sister chromatid exchange

Summary Development of 4-cell and of 8-cell mouse embryos and of morulae and blastocysts is inhibited in vitro by mouse serum but not by rat or human sera which also do not influence sister chromatid exchange in cultured morulae and blastocysts.     

On the in vitro behaviour of mouse submaxillary gland cells. II. Metabolic differences between male and female C3H mice

Summary Submaxillary gland cells from female C3H mice were isolated, cultivated in vitro and their metabolic properties compared with those of male derived cells. From the results it can be concluded that these cells retain their metabolic differences when grown in vitro.This work was supported by grant No. CT 73.00642.04 from the Consiglio Nazionale delle Ricerche (C.N.R.), Roma, Italy.     

Effects of beta-hydroxybutyrate on rat embryos grown in culture

In order to investigate further the relationship between maternal diabetes and fetal malformation, rat embryos were grown in vitro in the presence of beta-hydroxybutyrate, one of the ketone bodies produced by diabetics. At 10 mM, beta-hydroxybutyrate produced minor abnormalities and at 20 mM it produced major abnormalities in rat embryos.     

Insect hemocytes: Cells adapted to anaerobiosis

Summary Hemocytes from a free-living insect could be grown under strictly anoxic conditions. Their anaerobic metabolism was studied in vitro in such a cellular system.We thank Dr C. Remesy for analysing the volatile fatty acids and Drs P. Dejours and J. Girard for helpful discussions.     

Secificity of mouse endocervical cell response progesterone: presence of receptors]

The mouse cervical cell response to progesterone, corticosterone, and androgens was studied in vitro and comparatively by grafts on males. Contrary to the exocervical cells which responded more or less to the three steroid hormones, the endocervical cells responded exclusively to progesterone even in an estrogen free system. This result suggests the existence in the mouse endocervical cells of specific receptors to progesterone and indicates that the squamons cells of the uterine cervix have a different response to steroid hormones depending on where these cells are located.     

Comparative study of the effect of thymosin and supernatant from epithelial thymic cells on antibody production (author's transl)]

A thymic extract (TE) was prepared from supernatant of mice thymic epithelial cultures according to the purification of thymosin. TE and thymosin stimulated, in vitro, the immune response of mouse against deep red blood cells.     

Comparison of the in vitro development of mouse single blastomeres with and without the zona pellucida

No difference was observed during in vitro development between mouse single blastomeres with and without the zona pellucida, isolated from 2- and 4-cell stage eggs.     

Comparison of the in vitro development of mouse single blastomeres with and without the zona pellucida

Summary No difference was observed during in vitro development between mouse single blastomeres with and without the zona, pellucida, isolated from 2- and 4-cell stage eggs.     

Effect of insulin on immunological phagocytosis by macrophages.

It was shown that, in physiological concentrations, insulin enhances, in vitro, the immunological phagocytosis of sensitized sheep erythrocytes by cultured mouse peritoneal macrophages. Insulin seems to stimulate macrophage phagocytosis as a cholinomimetic agonist by increasing the intracellular levels of cyclic GMP.     

Suppressor effect induced by sodium periodate on the antibody response of mouse splenic cells in vitro : inhibition of this effect by sodium borohydride]

Mild oxidation of mouse spleen cells by sodium periodate induces blastogenesis. Concomitantly, the in vitro response of these cells to sheep red blood cells is inhibited. Exposure of spleen cells to sodium borohydride following periodate treatment reduces blastogenesis and restores the immune response.     

Resolution of small G1 and G2 populations of L1210 leukemia by flow microfluorometric analysis aided by velocity sedimentation

L1210 leukemic cells grown in vitro were subjected to kinetic analysis using a flow microfluorometer. A single broad peak was found for the DNA content distribution if unfractionated cells were used; prior fractionation using lg velocity sedimentation allowed the separation of small peaks with smaller (G1) and larger (G2) DNA contents from the dominant S phase peak with intermediate DNA content.     

Glutamine synthetase activity during mouse brain development

The specific activity of glutamine synthetase (GS) in mouse brain was 2-fold higher in the olfactory bulbs than in other regions. After birth, the specific activity of GS increased more rapidly in medulla oblongata and in olfactory bulbs, than in cerebral and cerebellar cortex. The activity of GS in primary cultures of brain hemispheres increased more slowly than in homogenates of whole brains. However, when astroblasts were treated in vitro with glucocorticoids or mouse brain extracts, GS activity reached 4 times the level measured in the homogenate of an adult mouse brain. We conclude that levels of GS activity may relate to the maturation of astrocytes, and propose that GS may be used as a marker of astrocytic maturation.     

Glutamine synthetase activity during mouse brain development

Summary The specific activity of glutamine synthetase (GS) in mouse brain was 2-fold higher in the olfactory bulbs than in other regions. After birth, the specific activity of GS increased more rapidly in medulla oblongata and in olfactory bulbs, than in cerebral and cerebellar cortex. The activity of GS in primary cultures of brain hemispheres increased more slowly than in homogenates of whole brains. However, when astroblasts were treated in vitro with glucocorticoids or mouse brain extracts, GS activity reached 4 times the level measured in the homogenate of an adult mouse brain. We conclude that levels of GS activity may relate to the maturation of astrocytes, and propose that GS may be used as a marker of astrocytic maturation.     

Influence of beta-aminoproprionitrile (BAPN) on cell growth and elastic fiber formation in cultures of auricular chondrocytes

Auricular chondrocytes isolated from 4-day-old rabbits and grown in vitro for 14 days, proliferated rapidly and produced a conspicuous network of elastic fibers. Beta-aminoproprionitrile (BAPN), which in vivo inhibits cross-linking of elastin, decreased the formation of elastic fibers at a concentration of 10-20 micrograms/ml and prevented formation at 40 micrograms/ml. At a concentration of 5 micrograms/ml only the so-called patches of elastin appeared to be absent. The inhibitory effect of BAPN on cell growth did not exceed 10%, which indicates that BAPN is only slightly harmful to auricular chondrocytes and can safely be used in studies on elastin deposition by these cells in vitro.     

Shoot regeneration fromAgrobacterium tumefaciens-induced tumors of a tropical timber tree,Fagraea fragrans

Summary Agrobacterium tumefaciens A208 with nopaline plasmid pTiT37 was used to obtain stem tumors on plantlets ofFagraea fragrans grown in vitro. Bacterial elimination and tissue proliferation were simultaneously achieved by growing tumors on cefatoxime medium. After some tissue growth the shoots regenerated. An examination of these showed the presence of nopaline, indicating genetic transformation by T-DNA.