title: Erythropoietin induces Ca2+ mobilization and contraction in rat mesangial and aortic smooth muscle cultures.
abstract: Reportedly, recombinant human erythropoietin (rhEpo) can induce constriction of isolated resistance vessels. We have studied whether rhEpo affects cytosolic calcium concentration, [Ca2+]i, and contraction of cultured smooth-muscle cells grown from rat renal corpuscles and aortae. rhEpo at high dose (> or = 20 U/mL) induced a transient increase in [Ca2+]i as detected by fura-2 fluorescence analysis. The number of cells responding with an increase in [Ca2+]i was dose-dependent. No significant changes of [Ca2+]i occurred when lower doses of rhEpo (< 20 U/mL) were applied. The effect of Epo on contraction was studied by phase-contrast microscopy. The number of cells responding with contraction was dose-dependent, too (76% mesangial cells contracting at 200 U rhEpo per mL). The receptor mechanism of this unusual action of Epo still needs to be clarified.
authors.affiliation: Institute of Physiology, University of Bonn, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Morakkabati
authors.forename: F
authors.initials: F
authors.lastname: Gollnick
authors.forename: R
authors.initials: R
authors.lastname: Meyer
authors.forename: J
authors.initials: J
authors.lastname: Fandrey
authors.forename: W
authors.initials: W
authors.lastname: Jelkmann
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology*; D001483:Base Sequence; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000494:pharmacology*; D015870:Gene Expression; D005920:Glomerular Mesangium / Q000166:cytology*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D009928:Organ Specificity; D051381:Rats; D017207:Rats, Sprague-Dawley; D017467:Receptors, Erythropoietin / Q000032:analysis / Q000235:genetics; D011994:Recombinant Proteins / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D017467:Receptors, Erythropoietin; D011994:Recombinant Proteins; D004921:Erythropoietin; D002118:Calcium