{"doi":"10.1042/bj2530081","title":"A novel tumour promoter, thapsigargin, transiently increases cytoplasmic free Ca2+ without generation of inositol phosphates in NG115-401L neuronal cells","abstract":"<jats:p>Thapsigargin, a sesquiterpene lactone with potent irritant and tumour-promoting activities, stimulates a rapid (within 15 s) transient increase in intracellular [Ca2+] in the NG115-401L neural cell line, as measured by the fluorescent indicator dye fura-2. This increase in cytoplasmic free [Ca2+] is concentration-dependent (ED50 around 20 nM) and occurs in the absence of extracellular Ca2+. Activation of NG115-401L cells by the inflammatory peptide bradykinin generates inositol phosphates, which parallel increases in intracellular [Ca2+]. However, the rise in cytoplasmic [Ca2+] stimulated by thapsigargin occurs in the absence of detectable production of inositol phosphates. Thapsigargin is unlike phorboid tumour promoters in that it has no action on two non-invasive indicators of phorbol stimulation of these cells, i.e. [3H]choline metabolite production and rise in intracellular pH. These data suggest that thapsigargin releases Ca2+ from an intracellular store by a novel mechanism, independent of the hydrolysis of phosphoinositides and concomitant activation of protein kinase C. Thus thapsigargin may provide a valuable tool for the analysis of intracellular signalling mechanisms.</jats:p>","journal":"Biochemical Journal","year":1988,"id":604932,"datarank":17.592989937242844,"base_score":5.84354441703136,"endowment":5.84354441703136,"self_citation_contribution":0.8765316625547042,"citation_network_contribution":16.71645827468814,"self_endowment_contribution":0.8765316625547042,"citer_contribution":16.71645827468814,"corpus_percentile":null,"corpus_rank":null,"citation_count":344,"citer_count":200,"citers_with_citation_signal":200,"citers_with_endowment":200,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1552230,"name":"S I Patterson","orcid":null,"position":1,"is_corresponding":false},{"id":1552231,"name":"O Thastrup","orcid":null,"position":2,"is_corresponding":false},{"id":1552232,"name":"M R Hanley","orcid":null,"position":3,"is_corresponding":false},{"id":147265,"name":"T R Jackson","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"A novel tumour promoter, thapsigargin, transiently increases cytoplasmic free Ca2+ without generation of inositol phosphates in NG115-401L neuronal cells","abstract":"<jats:p>Thapsigargin, a sesquiterpene lactone with potent irritant and tumour-promoting activities, stimulates a rapid (within 15 s) transient increase in intracellular [Ca2+] in the NG115-401L neural cell line, as measured by the fluorescent indicator dye fura-2. 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