title: Angiotensin II binding sites on micro-organisms contaminating cell cultures.
abstract: An angiotensin II (Ang II) binding site, distinct from AT1 and AT2, has been found in cell cultures of rat aortic smooth muscle and rat glomerular mesangium. It is characterized by a high affinity for Ang II (Kd 0.75 +/- 0.13 nM) and Ang I (Ki 0.72 +/- 0.12 nM), but a very low affinity for Ang III (Ki 31 +/- 5 microM). Ang(1-7) (Ki 1.01 +/- 0.26 nM) and Ang(1-6) (Ki 4.54 +/- 0.24 nM) are very selective for this site, with affinities more than 150- and 10,000-fold greater, respectively, than for AT1 or AT2. The selective angiotensin receptor subtype ligands losartan and L-158,809 (AT1), PD 123319 and CGP 42112A (AT2) were inactive. Binding to this site was abolished after the cells had been treated with the antibiotic mixture BM-Cyclin, suggesting that the site is located not on the cells, but on a cell culture contaminant. This has been identified as Acholeplasma laidlawii. Caution should therefore be exercised when interpreting Ang II-related data obtained from cells that have not been checked for Mollicute contamination.
authors: Research Department, Ciba-Geigy Limited, Basle, Switzerland.
authors: S
authors: S
authors: Whitebread
authors: J
authors: J
authors: Pfeilschifter
authors: H
authors: H
authors: Ramjoué
authors: M
authors: M
authors: de Gasparo
mesh_terms: D000128:Acholeplasma laidlawii / Q000378:metabolism*; D000804:Angiotensin II / Q000378:metabolism; D057911:Angiotensin Receptor Antagonists; D000818:Animals; D001713:Biphenyl Compounds / Q000494:pharmacology; D002478:Cells, Cultured; D004224:Diterpenes / Q000494:pharmacology; D004359:Drug Therapy, Combination / Q000494:pharmacology; D005920:Glomerular Mesangium / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007093:Imidazoles / Q000494:pharmacology; D019808:Losartan; D008911:Minocycline / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011945:Receptors, Angiotensin / Q000378:metabolism*; D013777:Tetrazoles / Q000494:pharmacology
chemical_list: D057911:Angiotensin Receptor Antagonists; D001713:Biphenyl Compounds; D004224:Diterpenes; D007093:Imidazoles; D011945:Receptors, Angiotensin; D013777:Tetrazoles; D000804:Angiotensin II; C074450:BM-cyclin; D008911:Minocycline; D019808:Losartan