Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2000-1-11
pubmed:abstractText
Membrane currents in isolated swine tracheal smooth muscle cells were investigated using a pipette solution containing BAPTA-Ca2+ buffer and Cs+ as the major cation. With a pipette solution containing 100 nM free Ca2+, acetylcholine (ACh; 1-100 microM), in a concentration-dependent manner, activated a current without inducing shortening of cells, although neither 1 mM histamine nor 1 microM leukotriene D4 activated the current (n = 7, n is the number of cells). The effect of 100 microM ACh was suppressed by pretreatment with 100 microM atropine (n = 6) or intracellular application of preactivated pertussis toxin at a concentration of 0.1 microg x mL(-1) (n = 8). Genistein (0.1-100 microM), in a concentration-dependent manner, suppressed the activation of the inward current by 100 microM ACh, whereas it did not significantly suppress that of the outward current (n = 6-8). With a pipette solution containing 50 nM free Ca2+, outward current, but not inward current, was activated by 100 microM ACh (n = 10). When the pipette solution had free Ca2+ concentrations greater than 50 nM, the inward current together with the outward current was activated. The ratio between the amplitude of the inward and outward currents was significantly increased as the free Ca2+ concentration in the pipette solution increased. The steady-state activation curve of the ACh-activated current with the 50 nM free Ca2+ pipette solution was fitted by a single Boltzmann distribution (Vh = +69.8 mV, k = -11.9 mV, n = 10). The activation time constant became smaller as the membrane potential was more depolarized (164.3+/-5.9 ms at +40 mV to 92.4+/-6.3 ms at +120 mV, n = 10). The reversal potential was not significantly changed by reducing extracellular Cl- concentration to one-tenth of the control (n = 8), suggesting that the current is a nonselective cationic current. These results suggest that ACh activates an outward nonselective cationic current via pertussis toxin-sensitive G-protein(s) coupled with muscarinic receptors. Involvement of genistein-sensitive tyrosine kinase in the activation process of the current is unlikely.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Acetylcholine, http://linkedlifedata.com/resource/pubmed/chemical/Atropine, http://linkedlifedata.com/resource/pubmed/chemical/Bronchodilator Agents, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Cations, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Genistein, http://linkedlifedata.com/resource/pubmed/chemical/Histamine, http://linkedlifedata.com/resource/pubmed/chemical/Leukotriene D4, http://linkedlifedata.com/resource/pubmed/chemical/Pertussis Toxin, http://linkedlifedata.com/resource/pubmed/chemical/Vasodilator Agents, http://linkedlifedata.com/resource/pubmed/chemical/Virulence Factors, Bordetella
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0008-4212
pubmed:author
pubmed:issnType
Print
pubmed:volume
77
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
796-805
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10588484-Acetylcholine, pubmed-meshheading:10588484-Animals, pubmed-meshheading:10588484-Atropine, pubmed-meshheading:10588484-Bronchodilator Agents, pubmed-meshheading:10588484-Calcium, pubmed-meshheading:10588484-Cations, pubmed-meshheading:10588484-Cells, Cultured, pubmed-meshheading:10588484-Dose-Response Relationship, Drug, pubmed-meshheading:10588484-Enzyme Inhibitors, pubmed-meshheading:10588484-Genistein, pubmed-meshheading:10588484-Histamine, pubmed-meshheading:10588484-Ion Transport, pubmed-meshheading:10588484-Leukotriene D4, pubmed-meshheading:10588484-Membrane Potentials, pubmed-meshheading:10588484-Muscle, Smooth, pubmed-meshheading:10588484-Patch-Clamp Techniques, pubmed-meshheading:10588484-Pertussis Toxin, pubmed-meshheading:10588484-Swine, pubmed-meshheading:10588484-Trachea, pubmed-meshheading:10588484-Vasodilator Agents, pubmed-meshheading:10588484-Virulence Factors, Bordetella
pubmed:year
1999
pubmed:articleTitle
Nonselective cationic currents activated by acetylcholine in swine tracheal smooth muscle cells.
pubmed:affiliation
Department of Physiology, Nihon University School of Medicine, Tokyo, Japan.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't