Occurrence of protein kinases NI and NII in human and porcine thyroids.

Cyclic nucleotide-independent protein kinases that preferentially phosphorylated casein and phosvitin as substrate were detected in the nuclei of human and porcine thyroid tissues, and compared with those from rat liver. Enzymes were extracted from the isolated nuclei with a buffer solution containing 0.4 M NaCl, and analyzed by DEAE-Sephadex and phosphocellulose column chromatographies.

Induction of ornithine decarboxylase in guinea-pig lymphocytes and its relation to phospholipid metabolism.

Treatment of lymphocytes with exogenous phospholipase C (phosphatidylcholine cholinephosphohydrolase, EC 3.1.4.

Effects of osmolality and potassium on motility of spermatozoa from freshwater cyprinid fishes.

Spermatozoa of freshwater Cyprinidae (goldfish, carp, crucian carp and dace) remained immotile when the semen was diluted in solutions of NaCl, KCl, mannitol or glucose iso-osmolar to the seminal plasma (300 mosmol kg-1). The spermatozoa became motile in media containing these solutes if the osmolality was lower than that of the seminal plasma, suggesting that motility is suppressed by the osmolality of the seminal plasma in the sperm duct and initiated by a decrease of osmolality upon spawning into fresh water. Potassium was a major component of seminal plasma, having a concentration 20-30 times higher than that in the blood plasma in goldfish and carp.

Effects of potassium and osmolality on spermatozoan motility of salmonid fishes.

In salmonid fishes, rainbow trout and masu salmon, and the plecoglossid fish, ayu, seminal plasma had an osmolality around 300 mosmol kg-1 isotonic to the blood plasma, and contained a higher concentration of potassium than the blood plasma. Spermatozoa of salmonid fishes were motile when semen was diluted 1:100 with solutions of sodium chloride or mannitol, over the osmotic range of 0-300 mosmol kg-1. They were immotile in sodium chloride solution containing several mM potassium.

Filter-binding assay procedure for thyroid hormone receptors.

An assay procedure for thyroid hormone receptor activity which used nitrocellulose membrane filters was developed. Receptor proteins, extracted from washed rat liver nuclei with a 0.4 M NaCl solution, were incubated with 125I-labeled thyroid hormone (T3), and filtered on the cellulose ester membranes under suction at 2 degrees C.

A set of non-histone proteins isolated from the nuclei of various rat tissues.

A set of non-histone proteins has been identified in the nuclei from liver, brain, spleen and testis tissues of the rat. Following moderate digestion of thoroughly washed nuclei with DNase I or micrococcal nuclease, EDTA was added to 5 mM to the reaction mixture and the preparation centrifuged. We found that the supernatant contained a limited amount of non-histone proteins (fraction S1).

Modulation of cholestatic factor production by serum components.

When lymph node cells from sensitized guinea pigs were stimulated in vitro with a specific antigen and their culture supernatant was injected into the mesenteric vein of rats, a marked decrease in bile flow was demonstrated. The treatment of activated lymphocytes with a higher molecular weight fraction of normal human serum Fr-1 and Fr-2 was shown to decrease the reduction of bile flow. Conversely, a lower molecular weight fraction of serum (Fr-3) was found to augment the reduction of bile flow.

Lipid peroxide formation in isolated hepatocytes by cytotoxic factors produced from lymphokine-activated macrophages.

When peripheral blood lymphocytes from patients with chronic active hepatitis were stimulated with liver specific lipoprotein (LSP), considerably higher frequencies of lymphocyte transformation and MIF production were induced. Peritoneal macrophages from guinea pigs were activated by lymphokine-containing lymphocyte culture supernatant and produced a cytotoxic (or cytostatic) factor acting on isolated hepatocytes in culture. The cytotoxic (or cytostatic) factor, which was fractionated by Sephadex G-75 column gel filtration followed by DEAE-cellulose column chromatography, had cytotoxic effect on isolated liver cells and produced a significant amount of lipid peroxide.

Induction of liver cell injury by antibody-dependent monocyte-mediated cytotoxicity in vitro.

The isolated liver cells coated with the anti-liver cell membrane antibody were damaged by incubation with the peripheral blood mononuclear cells. This was demonstrated by measuring the reduction of protein synthesis in the target liver cells. Adherent cells from the peripheral blood mononuclear cells were shown to have a sufficient capacity acting on the isolated liver cells as an effector when they were separated from the peripheral blood of normal and patients with acute or chronic active hepatitis.

Modulation of the macrophage hepatocytotoxicity and plasminogen activator activity of activated macrophages from guinea pigs by serum components from normal human and patients with liver diseases.

Activated macrophages (m phi) exhibited cytotoxic effects on isolated liver cells and produced plasminogen activator (PA) in vitro. A high molecular weight fraction of normal human serum (Fr-1) was shown to reduce the m phi-mediated hepatocytotoxicity and enhance the PA activity of activated m phi. Conversely, a lower molecular weight fraction of serum (Fr-3) was found to enhance the hepatotoxic potential and decrease the PA activity of activated m phi.

Induction of spermidine N1-acetyltransferase by sodium n-butyrate and phytohemagglutinin in bovine lymphocytes.

An increased activity of spermidine N1-acetyltransferase was induced in bovine lymphocytes by stimulation with either sodium n-butyrate or phytohemagglutinin (PHA). The acetylase activity was elevated by 2- to 3-fold 24 h after the addition of butyrate, whereas a similar increase of the enzyme activity was found 48 h after stimulation with PHA. When butyrate and PHA were added to the lymphocyte suspensions simultaneously, the peak of enzyme induction was observed at 24 h after the addition and the increase (9-fold) was found to be more than additive.

Immune responses to xanthan gum. I. The characteristics of lymphocyte activation by xanthan gum.

Xanthan gum (XG), a microbial polysaccharide produced extracellularly by fermentation of Xanthomonas campestris, has unique physical properties. We studied the effects of XG on murine lymphocytes in vitro and found that XG induced both a significant increase of DNA synthesis in mouse splenic B cells and thymocytes as well as polyclonal IgM and IgG antibody responses in B cells. XG-activated thymocytes, however, did not display helper or suppressor functions.

Studies on the mechanism of liver injury by macrophage-mediated cytotoxicity--partial purification of cytotoxic factor detected in the culture supernatant of activated macrophages.

The culture supernatant of activated lymphocytes was shown to contain macrophage activating factor (MAF), a kind of lymphokine, which activated the peritoneal macrophages prepared from guinea pigs. When the culture fluid of the MAF-activated macrophages was added to the isolated liver cells, a significant inhibition of their albumin biosynthesis was demonstrated. The active material was recovered in a definitive fraction by gel filtration using a Sephadex G-75 column and this was further fractionated into two fractions by DEAE-cellulose column chromatography, suggesting that at least two kinds of active substances existed.

Induction of ornithine decarboxylase by treatment of guinea pig lymphocytes with phospholipase C.

Treatment of guinea pig lymphocytes with Clostridium perfringens phospholipase C but not with Naja naja snake venom phospholipase A2 increased ornithine decarboxylase activity. The increase in ornithine decarboxylase activity was suppressed by actinomycin D or cycloheximide, suggesting that de novo syntheses of RNA and protein are necessary for the increase in the enzyme activity. These results suggest that the activation of phospholipase C rather than that of phospholipase A2 is responsible for induction of ornithine decarboxylase during lymphocyte transformation.