scholarly journals On the localisation of d-tubocurarine in rat liver lysosomes in vivo by electron microscopy and subcellular fractionation

1975 ◽  
Vol 289 (3) ◽  
pp. 251-256 ◽  
Author(s):  
Jeanette G. Weitering ◽  
Gerard J. Mulder ◽  
Dirk K. F. Meijer ◽  
Wim Lammers ◽  
Maarten Veenhuis ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Rat Liver ◽  
Subcellular Fractionation ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

scholarly journals Identification of targeting proteinase for rat α1-macroglobulin in vivo. Mast-cell tryptase is a major component of the α1-macroglobulin-proteinase complex endocytosed into rat liver lysosomes

1994 ◽  
Vol 298 (1) ◽  
pp. 79-85 ◽  
Author(s):  
A Tsuji ◽  
T Akamatsu ◽  
H Nagamune ◽  
Y Matsuda
Keyword(s):  
Mast Cell ◽  
Rat Liver ◽  
Cathepsin L ◽  
Deae Cellulose ◽  
Serine Proteinase ◽  
Mast Cell Tryptase ◽  
Diisopropyl Fluorophosphate ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

The alpha 1-macroglobulin-proteinase complex endocytosed into rat liver lysosomes was purified by a series of column chromatographic steps on concanavalin A-Sepharose, Sephacryl S-300, DEAE-cellulose and TSK gel DEAE-5PW columns. The complex contained no detectable alpha 2-macroglobulin. Studies on the substrate specificity indicated that the complex had tryptase-like activities towards various synthetic substrates, but no elastase, chymotrypsin, cathepsin-B and cathepsin-L activities. The proteinase activity was completely inhibited by di-isopropyl fluorophosphate, leupeptin and antipain, indicating that the proteinase bound to alpha 1-macroglobulin is a serine proteinase. Two protein bands (62 and 59 kDa) of the complex were labelled with [3H]diisopropyl fluorophosphate and both bands cross-reacted with anti-(mast-cell tryptase)antibody. These results suggest that mast-cell tryptase is a major targeting proteinase for alpha 1-macroglobulin in vivo. The main alpha-macroglobulin-proteinase complex in the adjuvant-treated rats was also the alpha 1-macroglobulin-tryptase complex, even though the plasma level of alpha 2-macroglobulin was elevated.

scholarly journals The effect of Trypan Blue, suramin and aurothiomalate on the breakdown of 125I-labelled albumin within rat liver lysosomes

1971 ◽  
Vol 121 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Malcolm Davies ◽  
J. B. Lloyd ◽  
F. Beck
Keyword(s):  
Rat Liver ◽  
Trypan Blue ◽  
Enzyme Inhibitors ◽  
Protein Hydrolysis ◽  
Particulate Carbon ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

1. A fraction enriched in lysosomes was prepared by centrifugation from the livers of rats that had been injected 0.5h before death with 125I-labelled albumin. When suspended in sucrose-protected buffer, pH7.4, and incubated at 22°C for 2h, the particles progressively released iodotyrosine into the medium. Albumin digestion did not occur if the particles were subjected to treatments known to break lysosomes or if particles from uninjected rats were incubated in medium containing 125I-labelled albumin. It is concluded that the observed production of iodotyrosine results from protein hydrolysis within intact heterolysosomes. 2. Particles from rats pre-treated with Trypan Blue, suramin or aurothiomalate released iodotyrosine more slowly than controls. Since these compounds are enzyme inhibitors that concentrate in liver lysosomes after administration in vivo, their effect is ascribed to intralysosomal inhibition of proteolysis. The doses used did not decrease endocytosis of albumin into liver or cause increased lysosome breakage during incubation, thus allowing some alternative explanations of the decreased proteolysis to be eliminated. Particulate carbon, a non-inhibitor that also concentrates in lysosomes, did not affect albumin hydrolysis.

Stabilization of rat liver lysosomes by (+)-cyanidanol-3 in vivo

1975 ◽  
Vol 24 (8) ◽  
pp. 905-909 ◽  
Author(s):  
Paul Niebes ◽  
Gilbert Ponard
Keyword(s):  
Rat Liver ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

scholarly journals Passive diffusion of non-electrolytes across the lysosome membrane

1989 ◽  
Vol 261 (2) ◽  
pp. 451-456 ◽  
Author(s):  
G P Iveson ◽  
S J Bird ◽  
J B Lloyd
Keyword(s):  
Hydrogen Bonding ◽  
Rat Liver ◽  
Liver Homogenate ◽  
Inverse Correlation ◽  
Protection Method ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes ◽  
Lysosome Membrane ◽  
Free Activity

An osmotic-protection method has been used to study the permeability of rat liver lysosomes to 43 organic non-electrolytes of formula weights ranging from 62 to 1000. A lysosome-rich centrifugal fraction of rat liver homogenate was resuspended in an unbuffered 0.25 M solution of test solute, pH 7.0, and incubated at 25 degrees C for 60 min. The free and total activities of 4-methylumbelliferyl N-acetyl-beta-D-glucosaminidase were measured after incubation for 0, 30 and 60 min. Three patterns of results were seen. In pattern A the percentage free activity remained low throughout the 60 min incubation, indicating little or no solute entry into the lysosomes. In pattern B, the percentage free activity was initially low, but rose substantially during the incubation, indicating solute entry. In pattern C there was not even initial osmotic protection, indicating very rapid solute entry. The rapidity of solute entry into the lysosomes showed no correlation with the formula weight, but a perfect inverse correlation with the hydrogen-bonding capacity of the solutes. The results, which can be used to predict the ability of further compounds to cross the lysosome membrane by unassisted diffusion, are discussed in the context of metabolite and drug release from lysosomes in vivo.

Studies in vitro and in vivo of the effects of chlorpromazine on rat liver lysosomes

1965 ◽  
Vol 14 (5) ◽  
pp. 769-775 ◽  
Author(s):  
Paul S. Guth ◽  
José Amaro ◽  
O.Z. Sellinger ◽  
Lloyd Elmer
Keyword(s):  
Rat Liver ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes
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