Growth regulation最新文献_第6页

A critical assessment of the use of microculture tetrazolium assays to measure cell growth and function. 使用微培养四氮唑测定法测量细胞生长和功能的关键评估。

Growth regulation Pub Date : 1995-06-01

N J Marshall, C J Goodwin, S J Holt

{"title":"A critical assessment of the use of microculture tetrazolium assays to measure cell growth and function.","authors":"N J Marshall, C J Goodwin, S J Holt","doi":"","DOIUrl":"","url":null,"abstract":"Microculture tetrazolium assays (MTAs) are being widely applied to probe the relationships between cell survival, growth, and differentiation and also to investigate associations between compromised cell metabolism, oxidative stress, and programmed cell death as occurs in apoptosis. MTAs rely upon the cellular reduction of tetrazolium salts to their intensely coloured formazans. The resulting colorimetric assays form the basis of exceptionally precise systems which are technically amenable and capable of a high throughput of samples. As a consequence, MTAs are being used to monitor responses to both extracellular activators and toxic agents in disciplines as diverse as radiobiology and endocrinology. We review the chemistry and histochemical applications of tetrazolium salts and subsequently discuss the criteria for their use in MTAs. These assays are one of the latest examples of the application of the tetrazolium/formazan system to cell biology. We outline current views on the mechanisms of the bioreduction of tetrazolium salts. These probably combine to reflect the integrated pyridine nucleotide dependent redox state of the cell. We try to illustrate how an understanding of these mechanisms helps to avoid some of the pitfalls of the MTA systems. There is now for example, extensive evidence that changes in cell culture environments, such as glucose supply or pH of the medium, influence the reduction of tetrazolium salts and thereby introduce artefacts into MTAs. Finally, we provide examples of situations in which MTAs can be used to complement other more established experimental systems. They then act as unique probes with which to investigate changes in the redox state of the cell. These changes are associated with regulation of cell growth, proliferation and differentiation and conversely, the different pathways leading to cell death.","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 2","pages":"69-84"},"PeriodicalIF":0.0,"publicationDate":"1995-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18633302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insulin-like growth factor binding protein production in human follicular thyroid carcinoma cells. 胰岛素样生长因子结合蛋白在人滤泡甲状腺癌细胞中的产生。

Growth regulation Pub Date : 1995-06-01

L K Bachrach, K Nänto-Salonen, P Tapanainen, R G Rosenfeld, S E Gargosky

{"title":"Insulin-like growth factor binding protein production in human follicular thyroid carcinoma cells.","authors":"L K Bachrach, K Nänto-Salonen, P Tapanainen, R G Rosenfeld, S E Gargosky","doi":"","DOIUrl":"","url":null,"abstract":"IGFs and IGF binding proteins (IGFBPs) appear to serve as regulators of non-malignant thyroid cells from several species, but little is known about their role in thyroid malignancy. We have examined IGFBP production and hormonal regulation in two human thyroid follicular carcinoma cell lines; FTC-133 line derived from a local tumor recurrence and FTC-236 cells from a tumor metastasis. Under basal conditions these cell lines produced IGFBP-3, IGFBP-4 and IGFBP-2. In both cell lines, EGF or TPA stimulated IGFBP-3 production while TSH or forskolin inhibited IGFBP-3 production and reduced the stimulation of IGFBP-3 seen with EGF or TPA. IGFBP-4 production was increased in the presence of TSH, forskolin, and EGF and was reduced by TPA. mRNA assessment revealed that IGFBP-3 mRNA, more abundant in FTC-236 than FTC-133 cells, increased in the presence of EGF or TPA, while IGFBP-4 mRNA content was increased in the presence of TSH, EGF, and forskolin. These results indicate that IGFBP production in human thyroid follicular carcinoma clones is under specific hormonal regulation. IGFBP-3 production is increased by dedifferentiation factors such as EGF and TPA and inhibited by TSH and forskolin, which enhance differentiated function. The highly specific regulation of IGFBP-3 and IGFBP-4 suggests a potential role for these peptides in modulating malignant thyroid growth.","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 2","pages":"109-18"},"PeriodicalIF":0.0,"publicationDate":"1995-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18549116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The development of an eluted stain bioassay (ESTA) for human growth hormone. 人生长激素洗脱染色生物测定法(ESTA)的建立。