Intracellular Lipids in Rabbit Ear Cartilage during Tissue Regeneration

1986 ◽  
Vol 127 (4) ◽  
pp. 249-254 ◽  
Author(s):  
J. Labandeira-Garcia ◽  
M. Guerra -Seijas
Keyword(s):  
Tissue Regeneration ◽  
Intracellular Lipids ◽  
Rabbit Ear ◽  
Ear Cartilage

scholarly journals Characterization of cathepsins in cartilage

1967 ◽  
Vol 105 (2) ◽  
pp. 549-557 ◽  
Author(s):  
S. Y. Ali ◽  
L. Evans ◽  
E. Stainthorpe ◽  
C. H. Lack
Keyword(s):  
Cathepsin B ◽  
Cartilage Matrix ◽  
Heat Inactivation ◽  
Ph Values ◽  
Fixed Weight ◽  
Exogenous Substrate ◽  
Nitrophenyl Phosphate ◽  
Rabbit Ear ◽  
Ear Cartilage

The presence of a cathepsin B-like enzyme in rabbit ear cartilage was established by the use of the synthetic substrates benzoyl-l-arginine amide and benzoyl-dl-arginine 2-naphthylamide. This was facilitated by using a technique that permits the incubation of a fixed weight of thin (18μ) cartilage sections with an appropriate exogenous substrate. The enzymic properties of cathepsin B in cartilage have been compared with an endogenous enzyme that liberates chondromucopeptide by degrading the cartilage matrix autocatalytically at pH5. Besides being maximally active at pH4·7, these cartilage enzymes are enhanced in activity by cysteine and inhibited by arginine analogues, iodoacetamide, chloroquine and mercuric chloride. They are not inhibited by EDTA, di-isopropyl phosphorofluoridate and diethyl p-nitrophenyl phosphate. When inhibiting the release of chondromucopeptide from cartilage at pH5, the arginine-containing synthetic substrates are hydrolysed simultaneously. These enzymes also share the same heat-inactivation characteristics at various pH values, being stable at acid pH and unstable at neutral and alkaline pH. The experimental evidence indicates that a cathepsin B-like enzyme may be partly responsible for the autolytic degradation of cartilage matrix at pH5.

scholarly journals STUDIES ON CARTILAGE

1960 ◽  
Vol 8 (1) ◽  
pp. 151-163 ◽  
Author(s):  
Huntington Sheldon ◽  
Robert A. Robinson
Keyword(s):  
Amorphous Material ◽  
Surface Membrane ◽  
Electrophoretic Pattern ◽  
Elastic Component ◽  
Elastic Tissue ◽  
Cell Cytoplasm ◽  
Elastic Cartilage ◽  
Rabbit Ear ◽  
The Matrix ◽  
Ear Cartilage

Electron microscope observations on rabbit ear cartilage following the administration of papain show that both the elastic component of the matrix and the amorphous material disappear leaving a matrix which consists of delicate fibrils which are presumed to be collagen. This unmasking of fibrils coincides with the appearance of an abnormal component in the electrophoretic pattern of the rabbit's serum. The chondrocytes show vacuoles in their cytoplasm which appear at the same time that the cells appear crenated in the light microscope. A ruffly appearance of the cell surface membrane coincides with this vacuolization, and vacuoles often appear open and in continuity with the extracellular space. The resurgence of the rabbit ear is accompanied by a reconstitution of both the amorphous material and the elastic component of the matrix. During this period numerous dilated cisternae of the endoplasmic reticulum which contain a moderately dense material are present in the chondrocyte cytoplasm. We have been unable to demonstrate a direct relationship between the elastic component of the matrix and a particular component of the chondrocyte cytoplasm, but it is clear that changes occur in the cartilage cell cytoplasm during both the depletion and reconstitution of the matrix. Previous studies on the effect of papain on elastic tissue are noted and the possible relationships between changes in the cells and matrix of this elastic cartilage are discussed.

scholarly journals The synthesis of low-molecular weight proteoglycans in rabbit-ear cartilage

FEBS Letters ◽  
1972 ◽  
Vol 26 (1-2) ◽  
pp. 336-340 ◽  
Author(s):  
A. Serafini-Fracassini ◽  
W.H. Stimson
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight ◽  
Rabbit Ear ◽  
Ear Cartilage

Thermochondroplasty of rabbit ear cartilage using the carbon dioxide laser

1994 ◽  
Vol 9 (4) ◽  
pp. 265-272 ◽  
Author(s):  
George Velegrakis ◽  
Miltos Volitakis ◽  
Irene Naumidi ◽  
John Bizakis ◽  
Panos Christodoulou ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Laser ◽  
Rabbit Ear ◽  
Ear Cartilage

scholarly journals Studies on the cathepsins in elastic cartilage

1969 ◽  
Vol 112 (4) ◽  
pp. 427-433 ◽  
Author(s):  
S. Y. Ali ◽  
Lois Evans
Keyword(s):  
Acid Phosphatase ◽  
Dna Content ◽  
Quantitative Method ◽  
Cathepsin C ◽  
Elastic Cartilage ◽  
Fixed Weight ◽  
Cathepsin Activity ◽  
Rabbit Ear ◽  
Ear Cartilage ◽  
Hydrolysis Of

1. The presence of several enzymes in rabbit ear cartilage was examined by a quantitative method that permits the incubation of a fixed weight of cartilage sections (18μm.) with an appropriate exogeneous substrate. 2. As the presence of cathepsins B and D in cartilage has already been established, evidence is now provided to show that cathepsins A and C are also present and are maximally active at pH5. 3. Cathepsin A was recognized by its hydrolysis of benzyloxycarbonyl-glutamyl-tyrosine and cathepsin C by its hydrolysis of glycyl-tyrosine amide; the cartilage also hydrolysed benzyloxycarbonyl-glutamyl-phenylalanine and benzoyl-dl-phenylalanine 2-naphthyl ester at pH5. 4. The acid phosphatase activity and the DNA content of cartilage have also been measured to provide a basis for comparison with the cathepsin activity of cartilage obtained from other sites and species.

scholarly journals Proteoglycan-degrading enzymes. A radiochemical assay method and the detection of a new enzyme cathepsin F

1977 ◽  
Vol 167 (3) ◽  
pp. 775-785 ◽  
Author(s):  
J T Dingle ◽  
A M J Blow ◽  
A J Barrett ◽  
P E N Martin
Keyword(s):  
Enzyme Concentration ◽  
Assay Method ◽  
Human Articular Cartilage ◽  
Ph Values ◽  
Degrading Enzymes ◽  
Incubation Experiments ◽  
Rabbit Ear ◽  
Ear Cartilage ◽  
Cathepsin F ◽  
Made In

1. Polyacrylamide beads containing entrapped 35S-labelled proteoglycan molecules have been prepared. 2. The measurement of release of radioactivity provides an extremely sensitive assay for proteoglycan-degrading enzymes, including proteinases and hyaluronidase. 3. The amount of label released is a logarithmic function of enzyme concentration or time of incubation. Experiments were made in an attempt to explain this. 4. Assays were made by the new method at several pH values, and with the inclusion of inhibitors to identify the proteoglycan-degrading enzymes of rabbit ear cartilage. 5. A previously undescribed proteinase active against proteoglycan at pH4.5 but unaffected by pepstatin, was discovered. The enzyme was named cathepsin F, and was partially purified and characterized; it was detected in human articular cartilage.

DOES GROWTH OCCUR IN YOUNG RABBIT EAR CARTILAGE GRAFTS TRANSPLANTED IN YOUNG RABBITS?

1962 ◽  
Vol 29 (3) ◽  
pp. 259-265 ◽  
Author(s):  
IQBAL WALIA ◽  
LYNDON A. PEER ◽  
WILIAM G. BERNHARD ◽  
HARRY W. GORDON
Keyword(s):  
Young Rabbit ◽  
Cartilage Grafts ◽  
Rabbit Ear ◽  
Ear Cartilage

scholarly journals STUDIES ON CARTILAGE

1962 ◽  
Vol 12 (3) ◽  
pp. 599-613 ◽  
Author(s):  
H. Sheldon ◽  
F. B. Kimball
Keyword(s):  
Golgi Apparatus ◽  
Electron Microscopic ◽  
Rabbit Ear ◽  
Ear Cartilage

Electron microscopic observations on chondrocytes from rabbit ear cartilage 72 hours after papain has been given intravenously show that many vacuoles in the Golgi apparatus contain a material with a speckled appearance. Some Golgi vacuoles also contain a material with a banded pattern which can be identified as a collagen. The significance of this observation is discussed.

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