title: Pharmacological activation changes stiffness of cultured human airway smooth muscle cells.
abstract: Using magnetic twisting cytometry (MTC), we measured the cytoskeletal stiffness of adherent human airway smooth muscle (HASM) cells. We hypothesized that modulation of actin-myosin interactions by application of contractile agonists would induce changes in cytoskeletal stiffness. In cells plated on high-density collagen, bradykinin (10(-6) M) and histamine (10(-4) M) increased stiffness by 85 +/- 15 and 68 +/- 16%, respectively. Increases in cell stiffness were also consistently observed after acetylcholine, substance P, and KCl. The bronchodilator agonists isoproterenol, prostaglandin E2, forskolin, dibutryl adenosine 3', 5'-cyclic monophosphate, and 8-bromoguanosine 3', 5'-cyclic monophosphate each caused a dose-dependent decrease in cell stiffness in unstimulated as well as bradykinin-treated cells. HASM cells plated on high-density collagen were stiffer than cells plated on low-density collagen (126 +/- 16 vs. 43 +/- 3 dyn/cm2) and developed more pronounced increases in stiffness in response to bradykinin as well as more pronounced decreases in stiffness in response to isoproterenol. These results are consistent with the hypothesis that modulation of actin-myosin interactions by application of contractile agonists causes changes in cytoskeletal stiffness of HASM cells. MTC may be a valuable tool for evaluating the mechanisms of pharmacomechanical coupling in airway smooth muscle cells in culture.
authors.affiliation: Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
authors.forename: R D
authors.initials: RD
authors.lastname: Hubmayr
authors.forename: S A
authors.initials: SA
authors.lastname: Shore
authors.forename: J J
authors.initials: JJ
authors.lastname: Fredberg
authors.forename: E
authors.initials: E
authors.lastname: Planus
authors.forename: R A
authors.initials: RA
authors.lastname: Panettieri
authors.forename: W
authors.initials: W
authors.lastname: Moller
authors.forename: J
authors.initials: J
authors.lastname: Heyder
authors.forename: N
authors.initials: N
authors.lastname: Wang
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000109:Acetylcholine / Q000494:pharmacology; D000199:Actins / Q000502:physiology; D001920:Bradykinin / Q000494:pharmacology*; D001993:Bronchodilator Agents / Q000494:pharmacology*; D003994:Bucladesine / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D003094:Collagen / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology*; D015232:Dinoprostone / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008280:Magnetics; D018721:Muscarinic Agonists / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects* / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D009218:Myosins / Q000502:physiology; D011189:Potassium Chloride / Q000494:pharmacology; D013373:Substance P / Q000494:pharmacology; D013997:Time Factors; D014132:Trachea / Q000187:drug effects / Q000502:physiology*
chemical_list: D000199:Actins; D001993:Bronchodilator Agents; D018721:Muscarinic Agonists; D005576:Colforsin; D015124:8-Bromo Cyclic Adenosine Monophosphate; D013373:Substance P; D003994:Bucladesine; D011189:Potassium Chloride; D006632:Histamine; D002217:Carbachol; D003094:Collagen; D009218:Myosins; D015232:Dinoprostone; D007545:Isoproterenol; D000109:Acetylcholine; D001920:Bradykinin