title: The role of the sarcoplasmic reticulum in the pure frequency potentiation: the effect of ryanodine.
abstract: The dependence of the contraction amplitude of the isolated papillary muscle of the guinea pig on the stimulation pattern is probably caused by a well working sarcoplasmic reticulum. This view is supported by the finding that the alkaloid ryanodine flattens the curve of the force-frequency relationship and abolishes the pure frequency potentiation. Ryanodine is said to destroy exclusively the connection between T-tubulus and sarcoplasmic reticulum.
mesh_terms: D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D005071:Evoked Potentials; D006168:Guinea Pigs; D009200:Myocardial Contraction / Q000187:drug effects*; D012433:Ryanodine / Q000494:pharmacology*; D012519:Sarcoplasmic Reticulum / Q000502:physiology*
chemical_list: D000470:Alkaloids; D012433:Ryanodine