title: [Ontogenic changes in cardiac rhythm during acute hypoxia in dogs and rabbits].
abstract: Newborn dogs and rabbits exhibit unequal reactivity of cardiac activity to acute hypoxia as compared to adult ones, being lesser in the newborn. In dogs, during postnatal life as well as during adaptation to hypoxia, tachycardic effect of atropine increases indicating the increase in vagal tone. In growing rabbits, cardiac rhythm decreases, the decrease being presumably due to changes in the tone of the sympathetic nervous system, since no significant changes were observed in cardiac activity during atropine administration.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001285:Atropine / Q000494:pharmacology; D004285:Dogs; D006321:Heart / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D000860:Hypoxia / Q000503:physiopathology*; D011817:Rabbits; D013045:Species Specificity
chemical_list: D001285:Atropine
vernacular_title: Izmeneniia serdechnogo ritma pri vozdeĭstvii ostroĭ gipoksii u sobak i krolikov v ontogeneza