Isolated liver cells prepared by an enzymatic technique were studied during incubation for 3–4 h. The number of cells capable of excluding trypan blue fell in a linear fashion over this period but oxygen consumption continued at a constant rate. Synthesis of albumin was demonstrated by a radial immunodiffusion technique, and incorporation of 3H-lysine into albumin was shown. Supplementation with amino acids was found necessary to enhance the production of albumin to a level of 0.85 ± 0.05 μg/h/106 cells.

Evidence is presented which shows that the effect of cholera toxin on HeLa cells was inhibited by a number of agents. These included ganglioside, whole human serum, purified fractions of serum and ethacrynic acid. Theophylline potentiated the effect of the toxin. It was proposed that the toxic effect was due to an increase of cyclic AMP within the cell. The serum factor responsible for inhibition was an α 1 α 2 - macroglobulin . Electron microscopy confirmed that cells affected by the toxin became rounded but no other differences were detected.

The possibility of using simple concentration gradients, formed by an automatic gradient former, was explored for the fractionation of human serum. Especial reference was paid to the isolation of albumin, prealbumin, haemopexin and transferrin. Prealbumin was most clearly resolved from albumin by a linear gradient whilst haemopexin and transferrin were partially resolved using a non-linear gradient with a very shallow initial rise in concentration. The disadvantages of the system and how these may be minimized using gamma emitters were pointed out.

1. The isolated perfused rat liver was used to study degradation rates of plasma albumin, transferrin and fibrinogen. 2. Constant fractional rates were observed for all three proteins even when the albumin concentration was drastically increased by the addition of large amounts to the perfusate pool. 3. Livers taken from rats deprived of dietary protein for 14-18 days showed greatly diminished fractional catabolic rates for albumin when perfused with blood from similarly deprived animals. 4. These rates could be restored to near-normal values by adding albumin or by perfusing with blood from normally fed rats. 5. These findings are consistent with the theory of pinocytosis as a step in the degradation of plasma proteins by hepatic parenchymal cells.

1. A method is described for the isolation of certain of the alpha(1)-globulins of rat plasma that are known to increase in concentration after tissue damage (acute-phase globulins). 2. Although apparently homogeneous when examined by disc electrophoresis at pH9, these proteins could be subdivided further by isoelectric fractionation. 3. Treatment with neuraminidase removed approx. 60% of the sialic acid originally present in these proteins and gave almost completely homogeneous material of decreased mobility when examined by disc electrophoresis in polyacrylamide gel. When subjected to immunoelectrophoresis this material gave a single arc. 4. The homogeneity of the isolated materials was examined by ultracentrifugation. The single peak thus found is consistent with molecular weights of 45000-46000. 5. The isolated materials were shown to be glycoproteins containing approx. 15% of carbohydrate, and to have isoelectric points in the range pH4.4-4.8.

1.1. An apparatus is described for continuous elution of substances as they are separated by electrophoresis in acrylamide gel. The elution buffer used for this purpose is pumped inward across the base of a cylinder of gel and then passes upward and out via a central capillary.2.2. Proteins and other large molecules are prevented from passing into the electrode buffer by means of a cellophane membrane. The membrane is rigidly mounted on a Perspex grid which forms part of an elution cell.3.3. Bubble formation in the membrane support grid is prevented by a magnetic stirrer operating in the lower electrode chamber.4.4. With 0.05 M borate buffer at pH 9.2 in the electrode vessels and for elution, and 0.37 M Tris buffer at pH 8.8 in the gel, substances with mobilities down to one-half of that of albumin can be separated and eluted from the gel during 24 hr of electrophoresis.

Research Article| September 01 1963 PREPARATION AND PROPERTIES OF RAT TRANSFERRIN AH GORDON; AH GORDON Search for other works by this author on: This Site PubMed Google Scholar LN LOUIS LN LOUIS Search for other works by this author on: This Site PubMed Google Scholar Biochem J (1963) 88 (3): 409–414. https://doi.org/10.1042/bj0880409 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation AH GORDON, LN LOUIS; PREPARATION AND PROPERTIES OF RAT TRANSFERRIN. Biochem J 1 September 1963; 88 (3): 409–414. doi: https://doi.org/10.1042/bj0880409 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Journal Search Advanced Search This content is only available as a PDF. © 1963 The Biochemical Society1963 Article PDF first page preview Close Modal You do not currently have access to this content.