title: Frequency-force relationship in dog atrial muscle as modified by acetylcholine.
abstract: The effects of acetylcholineee on the frequency-force relationship in isolated dog atria were investigated in a frequency range of 2-3.5 Hz. The atria were suspended in a bath and perfused with arterial blood from a carotid artery of a heparinized donor dog. The frequency-force relationship was uniformly and dose-dependently suppressed by infusion of acetylcholin in 3 different doses at the frequency range of 2-3.5 Hz, and acetylcholine did not induce a negative staircase.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D006325:Heart Atria; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*
chemical_list: D000109:Acetylcholine