title: The effect of external sodium on the contracture responses of pacemaker preparations of Leptodactylus insularis.
mesh_terms: D000818:Animals; D001001:Anura; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D006329:Heart Conduction System / Q000187:drug effects*; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D002110:Caffeine; D012964:Sodium; D011188:Potassium; D002118:Calcium