Effect of benz(a)pyrene and constant light exposure on rat liver lysosomes and biliary excretion of lysosomal enzymes

2005 ◽  
Vol 139 (1) ◽  
pp. 34-37 ◽  
Author(s):  
A. B. Pupyshev ◽  
E. M. Gutina ◽  
R. G. Fedina ◽  
S. V. Michurina ◽  
A. V. Shurlygina ◽  
...  
Keyword(s):  
Rat Liver ◽  
Biliary Excretion ◽  
Lysosomal Enzymes ◽  
Light Exposure ◽  
Constant Light ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

Pharmacologic perturbation of rat liver lysosomes: Effects on release of lysosomal enzymes and of lipids into bile

1988 ◽  
Vol 95 (4) ◽  
pp. 1088-1098 ◽  
Author(s):  
Richard B. Sewell ◽  
Susan A. Grinpukel ◽  
Alan R. Zinsmeister ◽  
Nicholas F. LaRusso
Keyword(s):  
Rat Liver ◽  
Lysosomal Enzymes ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

scholarly journals Hydrolysis of membrane phospholipids by phospholipases of rat liver lysosomes

1979 ◽  
Vol 182 (2) ◽  
pp. 599-606 ◽  
Author(s):  
Donald E. Richards ◽  
Robin F. Irvine ◽  
Rex M. C. Dawson
Keyword(s):  
Phospholipase C ◽  
Rat Liver ◽  
Lysosomal Enzymes ◽  
Microsomal Fraction ◽  
Water Soluble ◽  
Membrane Phospholipids ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes ◽  
Hydrolysis Of

(1) The hydrolysis of 32P- or myo-[2-3H]inositol-labelled rat liver microsomal phospholipids by rat liver lysosomal enzymes has been studied. (2) The relative rates of hydrolysis of phospholipids at pH4.5 are: sphingomyelin>phosphatidylethanolamine>phosphatidylcholine> phosphatidylinositol. (3) The predominant products of phosphatidylcholine and phosphatidylethanolamine hydrolysis are their corresponding lyso-compounds, indicating a slow rate of total deacylation. (4) Ca2+ inhibits the hydrolysis of all phospholipids, though only appreciably at high (>5mm) concentration. The hydrolysis of sphingomyelin is considerably less sensitive to Ca2+ than that of glycerophospholipids. (5) Analysis of the water-soluble products of phosphatidylinositol hydrolysis (by using myo-[3H]inositol-labelled microsomal fraction as a substrate) produced evidence that more than 95% of the product is phosphoinositol, which was derived by direct cleavage from phosphatidylinositol, rather than by hydrolysis of glycerophosphoinositol. (6) This production of phosphoinositol, allied with negligible lysophosphatidylinositol formation and a detectable accumulation of diacylglycerol, indicates that lysosomes hydrolyse membrane phosphatidylinositol almost exclusively in a phospholipase C-like manner. (7) Comparisons are drawn between the hydrolysis by lysosomal enzymes of membrane substrates and that of pure phospholipid substrates, and also the possible role of phosphatidylinositol-specific lysosomal phospholipase C in cellular phosphatidylinositol catabolism is discussed.

scholarly journals Studies on the permeability of rat liver lysosomes to carbohydrates

1969 ◽  
Vol 115 (4) ◽  
pp. 703-707 ◽  
Author(s):  
J B Lloyd
Keyword(s):  
Molecular Weight ◽  
Rat Liver ◽  
Substrate Concentration ◽  
Lysosomal Enzymes ◽  
Published Data ◽  
Progressive Loss ◽  
Liver Lysosomes ◽  
Before And After ◽  
Rat Liver Lysosomes ◽  
Free Activity

1. The latency of nitrocatechol sulphatase activity was measured in rat liver lysosomes before and after preincubation in 0·25m solutions of 25 different carbohydrates. 2. Preincubation in disaccharides, hexitols, gluconate, glucuronate or lactate gave little or no rise in ‘free’ sulphatase activity, indicating that these compounds do not easily penetrate the lysosomal membrane, but incubation in monosaccharides or the lower glycitols caused a progressive loss of latency. 3. Rates of increase in ‘free’ activity were taken as an indication of rates of solute penetration into lysosomes and were correlated with the structure and molecular weight of each sugar. 4. Additional evidence for non-penetration of maltose was obtained by demonstrating that the latency of lysosomal α-glucosidase is independent of substrate concentration employed. 5. The results are discussed in the light of published data on the latency of lysosomal enzymes.

scholarly journals Genistein inhibits glucose and sulphate transport in isolated rat liver lysosomes

2009 ◽  
Vol 103 (2) ◽  
pp. 197-205 ◽  
Author(s):  
Hsu-Fang Chou ◽  
Kun-Hung Chuang ◽  
Yi-Shan Tsai ◽  
Yi-Ju Chen
Keyword(s):  
Glucose Uptake ◽  
Glucose Transport ◽  
Rat Liver ◽  
Uptake Kinetics ◽  
Isolated Rat Liver ◽  
Sulphate Transport ◽  
Genistein Treatment ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes ◽  
Isolated Rat

Genistein and daidzein are known to have both beneficial and adverse effects on human health due to their many biological actions at the cellular level. Both isoflavones have been shown to inhibit GLUT-mediated glucose transport across the plasma membrane of mammalian cells. Since lysosomal membrane transport is essential for maintaining cellular homeostasis, the present study examined the effects of genistein and daidzein on glucose and sulphate transport in isolated rat liver lysosomes. Both genistein and daidzein significantly inhibited lysosomal glucose uptake. Genistein was a more potent glucose transport inhibitor than daidzein, with a half-maximum inhibitory concentration (IC50) of 45 μmol/l compared with 71 μmol/l for daidzein. Uptake kinetics of d-glucose showed a significant decrease in Vmax (control:genistein treat = 1489 (sem 91):507 (sem 76) pmol/unit of β-hexosaminidase per 15 s) without a change in Km. The presence of 50 μm-genistein in the medium also reduced glucose efflux from lysosomes preloaded with 100 mm-d-glucose. Genistein also inhibited lysosomal sulphate transport. Similar to its effects on glucose uptake kinetics, genistein treatment caused a significant decrease in sulphate uptake Vmax (control:genistein treat = 87 (sem 4):59 (sem 5) pmol/unit of β-hexosaminidase per 30 s), while the Km was not affected. The evidence provided by the present study suggests that the most likely mechanism of lysosomal glucose transport inhibition by genistein is via direct interaction between genistein and the transporter, rather than mediation by tyrosine kinase inactivation. Genistein likely has a similar mechanism of directly inhibiting sulphate transporter.

scholarly journals Interaction of salicylates with rat liver lysosomes

1969 ◽  
Vol 115 (5) ◽  
pp. 54P-54P ◽  
Author(s):  
D Robinson ◽  
P Willcox
Keyword(s):  
Rat Liver ◽  
Liver Lysosomes ◽  
Rat Liver Lysosomes

Interaction of rat liver lysosomes with basic polypeptides

FEBS Letters ◽  
1995 ◽  
Vol 369 (2-3) ◽  
pp. 217-220 ◽  
Author(s):  
Elena V. Rukavishnikova ◽  
Tatjana A. Korolenko ◽  
Toshihiro Sassa ◽  
Tatsuzo Oka ◽  
Saburou Horiuchi ◽  
...  
Keyword(s):  
Rat Liver ◽  
Liver Lysosomes ◽  
Basic Polypeptides ◽  
Rat Liver Lysosomes
Sign in / Sign up

Export Citation Format

Share Document