Premium
Antagonism of calcium by zinc in guinea‐pig isolated taenia caeci and trachealis muscle
Author(s) -
Sarriá B.,
Cortijo J.,
MartíCabrera M.,
Morcillo E.,
Esplugues J.
Publication year - 1989
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1989.tb11919.x
Subject(s) - trachealis muscle , verapamil , trifluoperazine , contraction (grammar) , chemistry , taenia coli , calcium , medicine , muscle contraction , endocrinology , antagonism , guinea pig , calmodulin , biology , biochemistry , receptor , charybdotoxin
1 In guinea‐pig isolated taenia caeci and trachealis bathed in a K + ‐rich, Ca 2+ ‐free medium, CaCl 2 (0.01–10 m m ) produced a concentration‐dependent contraction. Zn 2+ (0.01–1 m m ), Cd 2+ (0.01–1 m m ), verapamil (0.01–100 μ m ) and trifluoperazine (1–100 μ m ) were effective antagonists of CaCl 2 ‐induced responses. 2 Zn 2+ and Cd 2+ in concentrations from 0.01 to 1 m m were without effect on the tone of taenia and trachea in normal Tris solution. Conversely, Zn 2+ and Cd 2+ , in concentrations of 1 m m , caused contraction of these tissues in a K + ‐rich, Ca 2+ ‐free medium. Zn 2+ (1 m m )‐induced contractions of taenia and trachea were completely inhibited by verapamil (10 μ m ). 3 In taenia and trachea skinned of their plasma membranes, tension development induced by Ca 2+ (10 μ m or 1 μ m , respectively) was unaffected by verapamil (100 μ m ), whereas trifluoperazine (100 μ m ) depressed the maximal tension produced by Ca 2+ . Segments of skinned preparations contracted in response to low concentrations of Zn 2+ (10 μ m ) or Cd 2+ (10 μ m ). 4 It is concluded that Zn 2+ may suppress Ca 2+ ‐induced spasm by a direct action on the binding sites of the Ca 2+ channel.