Macrophages and reparation with special reference to silicosis.
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Biomedical subjects
Publications and source records attributed to E Kulonen.
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Prompted by Castor's investigations (4) on a connective-tissue-activating peptide (CTAP) we investigated the stimulative effect of synovial fluids and synovial-tissue extracts on the synthesis of collagen by incubated embryonic-chick tendon cells. The stimulative effect was greater with synovial-tissue extracts from more severe cases than with samples from patients having milder forms of the disease. There was no correlation between the stimulation by synovial fluids and synovial-tissue extracts from the same patient. The stimulative activity was lost at dialysis. A slight stimulation in the incorporation of glucosamine was also observed. Treatment of the patients with gold, chloroquine or steroids decreased the stimulating capacity. These effects seem to depend on factors different from those described by Castor. The differerences in the stimulant activity of samples from various groups cannot be entirely due to glutamine, which is one of the limiting nutrients of the embryonic-chick tendon cells.
The activities of 5'-nucleotidase, K+, Na+-activated Mg2+-dependent adenosine triphosphatase (ATPase) and leucine-beta-naphthylamidase were determined from 17 rheumatoid synovial fluids and from extracts of the corresponding synovial tissues. There was little correlation between the enzyme activities in the synovial fluids and those in the respective synovial-tissue extracts. In seropositive cases of rheumatoid arthritis the activities of 5'-nucleotidase and leucine-beta-naphthylamidase in the synovial-tissue extract were higher than in seronegative cases. Also, the ratios of the enzyme activities in the synovial fluids to the resepctive activities in synovial tissue were lower in the seropositive cases. The activity of 5'-nucleotidase in the synovial tissue decreased during gold treatment.
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1. A procedure was developed for the preparation of plasma membranes from experimental granulation tissue of the rat without the addition of enzymes. The yield is better than 20% and the purification at least tenfold. 2. Values are given for the activities of 5'-nucleotidase, Na-+, k-+-activated Mg-2+dependent adenosine triphosphatase and leucine beta-naphthylamidase, for lipid composition, and for the gel-electrophoretic patterns of proteins and glycoporteins in the membrane preparations. 3. The plasma membranes from the mature granulation tissue contain proportionally more protein in the lipid phase, but the specific activities of 5'-nucleotidase and Na-+,K-+-activated Mg-2+-dependent adenosine triphosphatase are smaller than in the proliferating tissue. Certain differences were repeatedly observed in the gel-electrophoretic patterns of the developmental phases. 4. The plasma membranes from the granulation tissue were compared with those from rat peritoneal macrophages and from embryonic-chick tendon cells.
Rats drank ethanol, on the average 1.20 g/100 g body weight, for various periods up to nearly 300 days. Experimental variables included a high-fat, low-protein diet, administration of additional ethanol by stomach tube, and CCl4 injections instead of ethanol. Growth was retarded by all the variables, especially by the high-fat, low-protein diet. The specific histological finding in the ethanol groups was the presence of Mallory bodies. Significant increase in total liver lipids was caused by ethanol, and rapid fat accumulation, inflammatory changes, and even fibrosis and cirrhosis by the high-fat, low-protein diet and the CCl4 injections. Ethanol raised the concentrations of collagen and soluble protein in the liver; the collagen content was increased also by the high-fat, low-protein diet and the CCl4 injections. The incorporation of proline to collagen was stimulated in incubated liver slices from both ethanol-treated and high-fat, low-protein-fed rats. These treatments also increased the concentration of free proline in the liver, thus augmenting the protein synthesis in fibroblasts.
Treatment with neuraminidase decreased the activity of Na+,K+-activated Mg2+-adenosine triphosphatase in plasma membranes isolated from experimental granulation tissue but not that of 5'-nucleotidase or leucine-beta-naphthylamidase. A temporary lowering of the pH of the plasma membrane suspension to 2-3 inactivated all three enzymes, which remained inactive after the pH had been readjusted to 7.4. Addition of dextran preparations to the membrane suspension decreased the activity of adenosine triphosphatase. Ethanol (0.4%) had a similar effect. These marker enzymes of plasma membranes were not affected by additions of hyaluronate, chondroitin sulfate, protein polysaccharide or soluble collagen. Serotonin stimulated the adenosine triphosphatase activity slightly. About 10-20% of the protein in the plasma membrane preparation was extracted with EDTA. This "fuzzy coat" fraction yielded a distinct gel-electrophoretic protein pattern. Hyaluronidase was not helpful in cleaving this surface layer from the plasma membranes.
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1. The intracellular volume in granulation tissue was about 15% of the total urea space. 2. The experimental granuloma has a greater ability to retain amino acids during the proliferation phase than later during the synthesis of collagen. 3. The synthesis of collagen and other proteins by granulation tissue is related to the concentrations of proline and glutamic acid in the medium. 4. The rate of synthesis of proline from glutamic acid in granulation-tissue slices is greatest during collagen synthesis. It is enhanced by lactate. 5. Extracellular cations influence the synthesis of collagen and ouabain is inhibitory. Synthesis of other proteins is less sensitive in this respect. 6. It is suggested that the synthesis of collagen is related to the supply of certain amino acids, especially proline, and hence to the redox balance, and also to the function of the cell wall.