Document Detail

Effects of the peptide toxin from Microcystis aeruginosa on intracellular calcium, pH and membrane integrity in mammalian cells.
MedLine Citation:
PMID:  3119237     Owner:  NLM     Status:  MEDLINE    
Extracts of water blooms of the toxic cyanobacterium Microcystis aeruginosa showed a range of toxicities not related to their ability to lyse mammalian red cells. The HPLC-purified heptapeptide toxin (mol. wt. 1035) from Microcystis did not lyse red cells at up to 500-fold higher concentrations than that required to kill mice. This toxin (LD50 110 micrograms/kg for male mice) was used to investigate in vitro effects on isolated thymocytes, hepatocytes, mammary alveolar cells, and cultured Swiss 3T3 fibroblasts. Thymocytes were stimulated to progressive Ca2+ entry by toxin (0.1-10 micrograms/ml), reaching a peak after approx. 5 min. No deformation, intracellular pH change, Trypan Blue entry or cell lysis was seen within 60 min at 37 degrees C. Hepatocytes were grossly deformed by the toxin, with a dose/response relationship between 0.1 and 1.0 microgram/ml. No progressive Ca2+ entry was observed on toxin addition, instead a rapid rise in intracellular Ca2+, presumably from intracellular sources. No change in intracellular pH, Trypan Blue exclusion or cell lysis was observed over 60 min. Mammary alveolar cells and 3T3 fibroblasts were unresponsive to toxin at the concentrations tested. No change in protein synthesis or nucleic acid synthesis in thymocytes was observed after culture with 0.5 or 5.0 micrograms/ml toxin. It was concluded that cytoskeletal changes in deformed hepatocytes (the target cells in vivo) demonstrated the most probable cellular basis for toxicity, rather than changes in membrane permeability or cell metabolism.
I R Falconer; M T Runnegar
Related Documents :
8466807 - A 48 kilodalton enterotoxin-related protein from clostridium perfringens vegetative and...
3119237 - Effects of the peptide toxin from microcystis aeruginosa on intracellular calcium, ph a...
2995027 - Autoradiographic detection of diphtheria toxin resistant mutants in human diploid fibro...
4913207 - Specific separation of cells on affinity columns.
24907447 - Specialized filopodia: at the 'tip' of morphogen transport and vertebrate tissue patter...
21242307 - Clusterin (apolipoprotein j), a molecular chaperone that facilitates degradation of the...
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Chemico-biological interactions     Volume:  63     ISSN:  0009-2797     ISO Abbreviation:  Chem. Biol. Interact.     Publication Date:  1987  
Date Detail:
Created Date:  1988-01-21     Completed Date:  1988-01-21     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0227276     Medline TA:  Chem Biol Interact     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  215-25     Citation Subset:  IM    
Department of Biochemistry, Microbiology and Nutrition, University of New England, Armidale, N.S.W., Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Calcium / metabolism*
Cell Membrane Permeability / drug effects*
Cells / drug effects*
Hydrogen-Ion Concentration*
Nucleic Acids / biosynthesis
Peptides, Cyclic / toxicity*
Protein Biosynthesis
Thymus Gland / cytology
Toxins, Biological / toxicity*
Verapamil / pharmacology
Reg. No./Substance:
0/Nucleic Acids; 0/Peptides, Cyclic; 0/Toxins, Biological; 52-53-9/Verapamil; 7440-70-2/Calcium

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Stress ulceration--clinical relevance of animal and human studies.
Next Document:  Stabilization of a reactive, electrophilic carcinogen, benzo[a]pyrene diol epoxide, by mammalian cel...