Proliferation In Kidney Research Articles

タバコ主流煙溶液がin vitroでのニワトリ胚の腎・肺細胞の増殖に及ぼす影響

タバコ主流煙溶液がin vitroでのニワトリ胚の腎・肺細胞の増殖に及ぼす影響

The pathogenesis of renal cortical tumours in rats fed 2% trisodium nitrilotriacetate monohydrate

To help assess the relationship between the renal toxicity and tumorigenicity associated with the administration of high doses of nitrilotriacetate (NTA) we have reviewed slides of sections from the kidneys of rats used in the National Cancer Institute bioassay of NTA. Trisodium NTA fed to Fischer 344 rats at 2% in the diet for 2 yr exerts a persistent toxic effect on the renal cortex which is manifested morphologically as vacuolation of proximal convoluted tubular epithelium and exacerbation of age-related nephrosis. Additionally, two pathogenic pathways leading to tumour formation in NTA-treated rats are suggested. A specific pathway initiated by vacuolation of proximal convoluted tubular epithelium leads to hyperplasia; reasons are advanced for the view that hyperplasia progresses to neoplasia. A possible concomitant pathway, which we suggest is nonspecific, is associated with regenerative proliferation in kidneys affected by severe age-related nephrosis. These data support the concept that there is a causal relationship between NTA-associated tubular toxicity and tumorigenicity. Doses of NTA that do not induce toxicity do not induce tubular tumours as demonstrated in this and in two other major long-term studies. Hence studies to investigate the pathogenesis of the toxic response provide an insight that suggests the basis for the development of NTA-associated tumours.

Protective effect of PSK, a protein-bound polysaccharide preparation against candidiasis in tumor-bearing mice.

In an experimental Candidiasis of tumor-bearing mice, the administration of PSK resulted in a prolongation of lifespan when mice were treated with PSK before infection or before and after infection. The viable fungal counts in kidneys 3 weeks after infection was found to be less in PSK-treated mice than the control mice without PSK administration. The delayed-type hypersensitivity reaction in infected tumor-bearing mice against Candida dead cells were stimulated to some extent by PSK administration. The fungal proliferation in kidneys of tumor-bearing mice at the early stage of infection was prevented by PSK administration. The experimental results involving chemotaxis and phagocytosis suggest that PSK administration restores or enhances the depressed protection of tumor-bearing mice against Candida infection, mostly due to potentiating the phagocytic activity of macrophages.

Cyclic AMP Stimulation of Macromolecular Synthesis in Reaggregates of Embryonic Organs

SummaryThe effect of DBcAMP on reaggregates of dispersed spinal and sympathetic ganglia, kidney, and liver cells is examined in order to define the nature of the growth acceleration that occurs when nerve is cultured with parenchymal tissue. Single cell suspensions prepared from chick embryo tissue are permitted to reaggregate on a rotary shaker. Measurement of the incorporation of labeled precursors into DNA and protein is used to monitor the effect of DBcAMP on the cultured reaggregates. The stimulatory effect of nerve on the growth and proliferation of kidney and liver reaggregates is mimicked by low concentrations of DBcAMP, suggesting a possible role for cyclic nucleotides in the growth processes of embryonic parenchymal organs.

Reappraisal of the use of a single dose of lead for the study of cell proliferation in kidney, liver, and lung

Three days after a single intraperitoneal injection of lead chloride (10 mg/kg) there was a twofold increase in the incorporation of [14C]thymidine into renal DNA. The observed elevation in DNA synthesis was preceded by an enhancement of [14 C]orotic acid incorporation into kidney RNA. In plumbic rats, the concentration of renal cyclic AMP was significantly reduced from day 3 through day 7, while the levels of putrescine, spermidine, and spermine remained generally unchanged throughout the experimental period. As in the case of kidney, lead treatment increased (twofold) orotic acid incorporation into RNA in liver and lung. In contrast, exposure to lead produced a reduction in the amount of thymidine incorporated into hepatic and pulmonary DNA. In both liver and lung, treatment with lead tended to lower the concentrations of three polyamines, putrescine, spermidine, and spermine. While exposure to this nonessential element decreased the level of cyclic AMP in hepatic tissue, a significant rise to 152% of control values was noted after 24 hr in lungs of plumbic animals. The data point to a degree of diversity in the metabolic responsiveness of certain tissues to lead exposure and suggest that this metal may not be an adequate experimental tool in the study of DNA replication.

Effects of kidney extract on the folic acid induced proliferation of the rat kidney

Single injection of a high dose of folic acid causes a proliferation of the kidney with an increase of the 3H-thymidine incorporation into the DNA of kidney cortex slices in rats. An aqueous extract from rat kidneys inhibits the increase of 3H-thymidine incorporation. The inhibition begins after 4 hours. The maximum effect is observed between 11 and 17 hours after injection of the kidney extract. The kidney extract also inhibits the increase of the DNA content per kidney after folic acid injection. Heart, lung, spleen and liver extracts and bovine serum albumin do not lead to inhibition of the 3H-thymidine incorporation into the DNA of kidney cortex sclices.

Effects of temperature on reptilian and other cells

ABSTRACT Reptilian cells, whether from adult organs or from entire embryos, may be cultured satisfactorily in Medium 199, to which is added 20 % foetal-calf serum. This medium, used at normal strength, is adequate even for the maintenance and proliferation of kidney and liver cells from an amphibian tadpole, but the performance of cells of lower vertebrates in the medium is inferior to that of mammalian and avian cells. When cultured for periods of at least 2 days, avian cells survive in an apparently normal fashion at higher temperatures (maximal, 45 °C) than reptilian; reptilian cells at higher temperatures than mammalian; and mammalian cells at higher temperatures than amphibian. There is a close correspondence between the lethal high temperatures of embryonic cells of diurnal lizards in culture (42-43 °C) and the known heatdeath temperatures of adult animals. Although inactive and contracted in culture at 3 °C, reptilian, avian and mammalian cells remain viable, often for prolonged periods without change of medium. The optimal temperature for cell culture is in the vicinity of 37·5 °C for reptilian, avian and mammalian cells, and about 31·5 °C for the amphibian cells used. Different types of cells from the same animal may have different temperature ranges. Epithelioid cells, for example, function better at higher temperatures than fibroblasts and in some cases may be shown to have a slightly higher maximal temperature. Dissociated epithelioid cells in culture may adopt a fibroblast-type of morphology, wandering on the glass surface with extended processes, or they may come together with other similar cells to form epithelial sheets. Fibroblasttype cells may contribute to monolayer formation, but do not join with epithelioid cells to form epithelial sheets.