The role of mechanical forces in dextral rotation during cardiac looping in the chick embryo

The size and organization of collagen fibrils in the extracellular matrix is an important determinant of tissue structure and function. The synthesis and deposition of collagen involves multiple steps which begin within the cell and continue in the extracellular space. High-voltage electron microscopic studies of the chick embryo cornea and tendon suggested that the extracellular space is compartmentalized by the fibroblasts for the regulation of collagen fibril, bundle, and tissue specific macroaggregate formation. The purpose of this study is to gather direct evidence regarding the association of the fibroblast cell surface with newly formed collagen fibrils, and to define the role of the fibroblast in the control and the precise positioning of collagen fibrils, bundles, and macroaggregates during chick tendon development.

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Hormonal regulation of hepatic fatty acid synthetase in chick embryo. Role of insulin.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)38048-1 ◽

1978 ◽

Vol 253 (7) ◽

pp. 2120-2125 ◽

Cited By ~ 5

Author(s):

V.C. Joshi ◽

S.J. Wakil

Keyword(s):

Fatty Acid ◽

Chick Embryo ◽

Hormonal Regulation ◽

Fatty Acid Synthetase ◽

Hepatic Fatty Acid

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The development of physiologic responsiveness to muscarinic agonists in chick embryo heart cell cultures. Role of high affinity receptors and sensitivity to guanine nucleotides.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)42800-6 ◽

1984 ◽

Vol 259 (12) ◽

pp. 7382-7390

Author(s):

J B Galper ◽

L C Dziekan ◽

T W Smith

Keyword(s):

Chick Embryo ◽

Cell Cultures ◽

Guanine Nucleotides ◽

Heart Cell ◽

Muscarinic Agonists ◽

High Affinity ◽

Chick Embryo Heart ◽

Embryo Heart

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The Role of Mechanical Tension in Neurons

MRS Proceedings ◽

10.1557/proc-1274-qq01-06 ◽

2010 ◽

Vol 1274 ◽

Cited By ~ 1

Author(s):

Taher Saif ◽

Jagannathan Rajagopalan ◽

Alireza Tofangchi

Keyword(s):

Mechanical Response ◽

Mechanical Forces ◽

Active Tension ◽

Mechanical Tension ◽

Deformation Response ◽

Linear Force ◽

Tension Regulation ◽

Over Time

AbstractWe used high resolution micromechanical force sensors to study the in vivo mechanical response of embryonic Drosophila neurons. Our experiments show that Drosophila axons have a rest tension of a few nN and respond to mechanical forces in a manner characteristic of viscoelastic solids. In response to fast externally applied stretch they show a linear force-deformation response and when the applied stretch is held constant the force in the axons relaxes to a steady state value over time. More importantly, when the tension in the axons is suddenly reduced by releasing the external force the neurons actively restore the tension, sometimes close to their resting value. Along with the recent findings of Siechen et al (Proc. Natl. Acad. Sci. USA 106, 12611 (2009)) showing a link between mechanical tension and synaptic plasticity, our observation of active tension regulation in neurons suggest an important role for mechanical forces in the functioning of neurons in vivo.

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Decrease in hepatic cytochrome P-450 by cobalt. Evidence for a role of cobalt protoporphyrin

Biochemical Journal ◽

10.1042/bj2040103 ◽

1982 ◽

Vol 204 (1) ◽

pp. 103-109 ◽

Cited By ~ 24

Author(s):

J F Sinclair ◽

P R Sinclair ◽

J F Healey ◽

E L Smith ◽

H L Bonkowsky

Keyword(s):

Chick Embryo ◽

Gel Electrophoresis ◽

Polyacrylamide Gel Electrophoresis ◽

Polyacrylamide Gel ◽

Cobalt Protoporphyrin ◽

Cytochrome P 450 ◽

Hepatic Cytochrome

Exposure of cultured chick-embryo hepatocytes to increasing concentrations of CoCl2 in the presence of allylisopropylacetamide results in formation of cobalt protoporphyrin, with a reciprocal decrease in haem and cytochrome P-450. Treatment of rats with CoCl2 (84 mumol/kg) and 5-aminolaevulinate (0.2 mmol/kg) also results in formation of cobalt protoporphyrin and a decrease in cytochrome P-450 in the liver. Hepatic microsomal fractions from rats treated with phenobarbital, CoCl2 and 5-aminolaevulinate were analysed by polyacrylamide gel electrophoresis. Cobalt protoporphyrin was associated mainly with proteins of 50000-53000 mol.wt. The results suggest that the formation of cobalt protoporphyrin occurred at the expense of the synthesis of haem, leading to a decrease in cytochrome P-450. Furthermore, the cobalt protoporphyrin that was formed may itself have been incorporated into apocytochrome P-450.

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Role of carbohydrates in protein secretion and turnover: Effects of tunicamycin on the major cell surface glycoprotein of chick embryo fibroblasts

Cell ◽

10.1016/0092-8674(78)90320-3 ◽

1978 ◽

Vol 13 (3) ◽

pp. 461-473 ◽

Cited By ~ 262

Author(s):

Kenneth Olden ◽

Robert M. Pratt ◽

Kenneth M. Yamada

Keyword(s):

Chick Embryo ◽

Cell Surface ◽

Protein Secretion ◽

Surface Glycoprotein ◽

Cell Surface Glycoprotein ◽

Embryo Fibroblasts

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Activités cholinestérasiques dans le foie de Poulet Rôle de l'endoderme dans l'apparition d'activités cholinestérasiques dans la composante mésenchymateuse du tissu hépatique

Development ◽

10.1242/dev.26.3.481 ◽

1971 ◽

Vol 26 (3) ◽

pp. 481-495

Author(s):

Par Elisabeth Houssaint ◽

Nicole Le Douarin

Keyword(s):

Endothelial Cells ◽

Chick Embryo ◽

Cholinesterase Activity ◽

Enzymic Activity ◽

The Body ◽

Hepatic Tissue ◽

Experimental Procedure ◽

Septum Transversum ◽

Cholinesterase Activities

Cholinesterases in the chick liver. The role of the endoderm in the appearance of the activity of cholinesterases in the hepatic mesenchyme The histochemical method of Koelle & Friedenwald (1949), as modified by Gerebtzoff (1953), has been used to investigate the distribution of cholinesterases in the chick embryonic and adult liver. Non-specific cholinesterases and, in a lower proportion acetylcholinesterase, have been detected in the endothelial cells of blood sinusoids of both adult and embryonic hepatic tissue. The hepatocytes do not show any cholinesterase activity. Cholinesterases appear precociously in the liver mesenchyme, since they already occur in the septum transversum of the 3-day-old chick embryo. An experimental procedure preventing the invasion of the hepatic mesenchymal Anlage by the endodermic cords has been used. The experimentally isolated hepatic mesenchyme shows an important cholinesterase activity; therefore this activity does not depend on the presence of the hepatocytes. The grafting of the determined hepatic endodern in the somatopleura of the 3-day-old chick embryo results in the development of hepatic tissue in the body wall. In this experimentally produced liver, cholinesterase activities are present in the endothelial cells which have arisen from somatopleura mesenchymal cells, though normally somatopleural mesenchyme does not possess these enzymes. The role of the endoderm in the appearance of this enzymic activity in the somatopleural mesenchyme is discussed.

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