Difference between revisions of "Hogeboom 1948 J Biol Chem"
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SUMMARY | SUMMARY | ||
# The mitochondria of rat liver cells, when released by homogenization into water or isotonic NaCl solution, are altered to such an extent that they are not morphologically identifiable. When released into strong solutions of sucrose (0.8 to 1.0 M), however, they show the morphological and staining properties characteristic of normal intracellular mitochondria. Cytological studies of rat liver homogenates prepared in solutions of sucrose and other compounds at several concentrations indicate that the proportion of morphologically intact mitochondria, both extracellular and intracellular, increases with increasing concentration of solute and is related to the osmotic pressure of the medium. Sedimentation of mitochondria from homogenates prepared in 0.88 M sucrose and washing with the same medium does not result in any change in their morphological or staining properties. | |||
# A procedure for the centrifugal fractionation of rat liver homogenates prepared in 0.88 M sucrose is described. By this procedure it is possible to obtain mitochondria in suspensions that are apparently free from other cellular components. In the experiments reported, 65 to 82 per cent of the succinoxidase activity of the original homogenate was recovered in the mitochondria, the remainder of the enzyme activity being present in a fraction containing nuclei and unbroken liver cells. On the basis of cytological observations and additional chemical data, it is concluded that mitochondria contain all of the succinoxidase present in the cytoplasm of the liver cell and probably all of the succinoxidase present in the entire cell.It is further estimated that 34 per cent of the total nitrogen and 19 per cent of the pentosenucleic acid (PNA) of whole liver can be accounted for in mitochondria. The succinoxidase Q02 (microliters of 02 per hour per mg. of nitrogen) and the ratio, micrograms of PNA phosphorus to mg. of nitrogen, are approximately 2100 and 13, respectively, for mitochondria. These values remain constant on repeated sedimentation and resuspension of mitochondria in 0.88 M sucrose. | |||
liver | # Submicroscopic particulate material of a diameter of approximately | ||
100 rnp or greater was also isolated from 0.88 M sucrose homogenates of rat liver by means of prolonged centrifugation at high speed. Suspensions of this material are opalescent, show birefringence of flow, and contain no succinoxidase activity. The PNA content of the submicroscopic particles is characteristically high, the ratio, micrograms of PNA phosphorus to mg. of nitrogen, being approximately 58 for this fraction. It is estimated that the submicroscopic particles account for approximately 20 per cent of the total nitrogen and 50 per cent of the PNA of whole liver. | 100 rnp or greater was also isolated from 0.88 M sucrose homogenates of rat liver by means of prolonged centrifugation at high speed. Suspensions of this material are opalescent, show birefringence of flow, and contain no succinoxidase activity. The PNA content of the submicroscopic particles is characteristically high, the ratio, micrograms of PNA phosphorus to mg. of nitrogen, being approximately 58 for this fraction. It is estimated that the submicroscopic particles account for approximately 20 per cent of the total nitrogen and 50 per cent of the PNA of whole liver. | ||
Revision as of 18:13, 7 June 2012
| Hogeboom GH, Schneider WC, Palade GE (1948) Cytochemical studies of mammalian tissues; isolation of intact mitochondria from rat liver; some biochemical properties of mitochondria and submicroscopic particulate material. J Biol Chem 172: 619-635. |
Hogeboom GH, Schneider WC, Palade GE (1948) J Biol Chem
Abstract: See Free Text • Keywords: liver, mitochondria
Labels:
Organism: Rat
Tissue;cell: Hepatocyte; Liver"Hepatocyte; Liver" is not in the list (Heart, Skeletal muscle, Nervous system, Liver, Kidney, Lung;gill, Islet cell;pancreas;thymus, Endothelial;epithelial;mesothelial cell, Blood cells, Fat, ...) of allowed values for the "Tissue and cell" property.
Preparation: Isolated Mitochondria"Isolated Mitochondria" is not in the list (Intact organism, Intact organ, Permeabilized cells, Permeabilized tissue, Homogenate, Isolated mitochondria, SMP, Chloroplasts, Enzyme, Oxidase;biochemical oxidation, ...) of allowed values for the "Preparation" property.
Made history
SUMMARY
- The mitochondria of rat liver cells, when released by homogenization into water or isotonic NaCl solution, are altered to such an extent that they are not morphologically identifiable. When released into strong solutions of sucrose (0.8 to 1.0 M), however, they show the morphological and staining properties characteristic of normal intracellular mitochondria. Cytological studies of rat liver homogenates prepared in solutions of sucrose and other compounds at several concentrations indicate that the proportion of morphologically intact mitochondria, both extracellular and intracellular, increases with increasing concentration of solute and is related to the osmotic pressure of the medium. Sedimentation of mitochondria from homogenates prepared in 0.88 M sucrose and washing with the same medium does not result in any change in their morphological or staining properties.
- A procedure for the centrifugal fractionation of rat liver homogenates prepared in 0.88 M sucrose is described. By this procedure it is possible to obtain mitochondria in suspensions that are apparently free from other cellular components. In the experiments reported, 65 to 82 per cent of the succinoxidase activity of the original homogenate was recovered in the mitochondria, the remainder of the enzyme activity being present in a fraction containing nuclei and unbroken liver cells. On the basis of cytological observations and additional chemical data, it is concluded that mitochondria contain all of the succinoxidase present in the cytoplasm of the liver cell and probably all of the succinoxidase present in the entire cell.It is further estimated that 34 per cent of the total nitrogen and 19 per cent of the pentosenucleic acid (PNA) of whole liver can be accounted for in mitochondria. The succinoxidase Q02 (microliters of 02 per hour per mg. of nitrogen) and the ratio, micrograms of PNA phosphorus to mg. of nitrogen, are approximately 2100 and 13, respectively, for mitochondria. These values remain constant on repeated sedimentation and resuspension of mitochondria in 0.88 M sucrose.
- Submicroscopic particulate material of a diameter of approximately
100 rnp or greater was also isolated from 0.88 M sucrose homogenates of rat liver by means of prolonged centrifugation at high speed. Suspensions of this material are opalescent, show birefringence of flow, and contain no succinoxidase activity. The PNA content of the submicroscopic particles is characteristically high, the ratio, micrograms of PNA phosphorus to mg. of nitrogen, being approximately 58 for this fraction. It is estimated that the submicroscopic particles account for approximately 20 per cent of the total nitrogen and 50 per cent of the PNA of whole liver.
