Lectin receptor sites on rat liver cell nuclear membranes

1976 ◽  
Vol 22 (2) ◽  
pp. 335-344
Author(s):  
I. Virtanen ◽  
J. Wartiovaara
Keyword(s):  
Rat Liver ◽  
Liver Cell ◽  
Liver Cells ◽  
Nuclear Surface ◽  
Con A ◽  
Lectin Receptor ◽  
Nuclear Membranes ◽  
Cytoplasmic Surface ◽  
Receptor Sites ◽  
Rat Liver Cells

The presence and localization of lectin receptor sites on rat liver cell nuclear and other endomembranes was studied by light and electron microscopy using fluorescein and ferritin-coupled lectin conjugates. Isolated nuclei labelled with fluorescein-conjugated Concanavalin A (Con A) or wheat germ agglutinin (WGA) often showed membrane staining, which sometimes was especially bright on small stretches of the nuclear surface. Unlabelled nuclei and nuclei with a complete ring fluorescence were also seen. The nuclear fluorescence corresponded in intensity to that seen on the surface of isolated rat liver cells. Con A-ferritin particles were seldom detected on the cytoplasmic surface of the intact nuclear envelope. However, at places where the 2 leaflets of the envelope were widely separated or where the outer nuclear membrane was partly torn away, heavy labelling was seen on the cisternal surface of both the inner and outer nuclear membranes. Labelling with Con A-ferritin was also found on the cisternal side of rough endoplasmic reticulum present in the specimens. No labelling was seen on the cytoplasmic surface of mitochondrial outer membrane. The results demonstrate the presence of binding sites for Con A and WGA in nuclei and an asymmetric localization of these sites on the cisternal side of ribosome-carrying endomembranes in rat liver cells.

Effects of Hypophysectomy on the Fine Structure of Rat Liver Cells

1967 ◽  
Vol 25 ◽  
pp. 156-157
Author(s):  
Robert R. Cardell
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Rat Liver ◽  
Liver Cell ◽  
Anterior Pituitary ◽  
Liver Cells ◽  
Biochemical Studies ◽  
Liver Functions ◽  
Rat Liver Cells ◽  
And Control

Hypophysectomy of the rat renders this animal deficient in the hormones of the anterior pituitary gland, thus causing many primary and secondary hormonal effects on basic liver functions. Biochemical studies of these alterations in the rat liver cell are quite extensive; however, relatively few morphological observations on such cells have been recorded. Because the available biochemical information was derived mostly from disrupted and fractionated liver cells, it seemed desirable to examine the problem with the techniques of electron microscopy in order to see what changes are apparent in the intact liver cell after hypophysectomy. Accordingly, liver cells from rats which had been hypophysectomized 5-120 days before sacrifice were studied. Sham-operated rats served as controls and both hypophysectomized and control rats were fasted 15 hours before sacrifice.

Combined Effect of Oxygen and Ammonia on the Kinetics of Ammonia Elimination and Oxygen Consumption of Adherent Rat Liver Cells

2002 ◽  
Vol 25 (2) ◽  
pp. 151-157 ◽  
Author(s):  
G. Catapano ◽  
L. De Bartolo
Keyword(s):  
Oxygen Consumption ◽  
Dissolved Oxygen ◽  
Rat Liver ◽  
Liver Cell ◽  
Ammonia Concentration ◽  
Liver Cells ◽  
Urea Synthesis ◽  
High Ammonia ◽  
Rat Liver Cells ◽  
Oxygen Tensions

Oxygen is essential for the survival of isolated liver cells and its concentration is known to affect their viability and function. Recent reports have also shown that ammonia is eliminated at a rate depending on its concentration and that high ammonia concentrations may be cytotoxic to rat liver cells. Nonetheless, little quantitative information on the effect of either metabolite on liver cell reaction kinetics is available although important to the design of bioreactors for bioartificial livers (BALs). In this investigation, we characterized the dependence of the rate of oxygen consumption (OCR), ammonia elimination (AER) and urea synthesis (USR) on ammonia concentration at physiological (i.e., 43 and 72 mmHg) and supra-physiological (i.e., 134 mmHg) dissolved oxygen tensions. To this purpose, isolated rat liver cells were cultured in adhesion on collagen in a continuous-flow bioreactor optimised for the kinetic characterisation of liver cell metabolic reactions. Rates of the investigated reactions generally increased with increasing ammonia concentrations. OCR and USR significantly increased with increasing dissolved oxygen tensions, particularly at high ammonia concentrations. The actual dissolved oxygen tension significantly influenced also OCR and USR dependence on ammonia concentration. The best-fit rate equations were used to show that, at the beginning of the treatment with a bioreactor packed with primary liver cells, high ammonia concentration in the blood may cause large hypoxic zones in the bioreactor as a result of its effect on OCR. This suggests that plasma (or blood) detoxification prior to entering the bioreactor might enhance BAL efficacy by preserving a large fraction of the available cell activity for longer times.

Role of cell surface receptor mobility in concanavalin A-induced agglutination of Novikoff hepatoma and normal rat liver cells

1980 ◽  
Vol 42 (1) ◽  
pp. 169-182
Author(s):  
P. Mastromarino ◽  
G. Neri ◽  
A. Serra ◽  
E.F. Walborg
Keyword(s):  
Cell Surface ◽  
Rat Liver ◽  
Liver Cells ◽  
Cell Surface Receptor ◽  
Lateral Mobility ◽  
Con A ◽  
Novikoff Hepatoma ◽  
Surface Fluorescence ◽  
Rat Liver Cells ◽  
Normal Rat

The relationshio between Con A-receptor mobility and Con A-induced agglutination of Novikoff hepatoma and normal rat liver cells was investigated. Novikoff cells, incubated with fluorescein-labelled Con A at 3 degrees C displayed uniform, ring-like surface fluorescence. Increasing the temperature of the cells to 37 degrees C caused capping of Con A receptors in approximately 65% of the cells, a phenomenon that could be prevented by prefixing the cells with glutaraldehyde. In spite of these variations in Con A-receptor distribution, Con A-induced agglutination was remarkably constant over a temperature range from 3 to 37 degrees C. In contrast to Novikoff cells, normal hepatocytes displayed a uniform, ringlike surface fluorescence at both 3 and 37 degrees C. No capping was observed. However, hepatocytes, similar to Novikoff cells, were agglutinable by low concentrations of Con A. These findings indicate that, in this model system, Con A-induced cytoagglutination is not dependent upon long-range lateral mobility of Con A receptors. The qualitative differences in the lateral mobility of cell-surface Con A receptors of normal and malignant rat liver cells may represent a marker for neoplastioc transformation during hepatocarcinogenesis, adaptation to growth in ascitic form, or progression of a tumour to a more malignant state.

Isolation of rat liver cells containing Concanavalin-A receptor sites

FEBS Letters ◽  
1974 ◽  
Vol 47 (1) ◽  
pp. 11-14 ◽  
Author(s):  
Marcos Rojkind ◽  
María Luisa Portales ◽  
María Eugenia Cid
Keyword(s):  
Rat Liver ◽  
Concanavalin A ◽  
Liver Cells ◽  
Receptor Sites ◽  
Rat Liver Cells

Heterogeneity of carboxylesterases in rat liver cells

1992 ◽  
Vol 44 (4) ◽  
pp. 827-829 ◽  
Author(s):  
Rolf Gaustad ◽  
Trond Berg ◽  
Frode Fonnum
Keyword(s):  
Rat Liver ◽  
Liver Cells ◽  
Rat Liver Cells
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