title: [A simple and new type of drop recorder mainly applied in the experiment of frog heart].
abstract: OBJECTIVE
  To introduce the manufacture and use of a simple, new type of drop recorder of frog heart.
  
  
  METHODS
  To improve the perfusion device of (see text for symbol) and Straub method. Two electrodes of drop recorder were fixed in an injector of 20 ml. The input tube, output tube and resistance tube were all made of plastic material.
  
  
  RESULTS
  This device could be used to observe effects of preload, after-load, hormone and electrolyte on the cardiac output in isolated frog heart.
  
  
  CONCLUSIONS
  The new type of drop recorder was economical and could be easily operated, it could be also connected to computer. Using the new type of drop recorder, effects of various physical and chemical factors on cardiac function could be observed directly, accurately.
authors.affiliation: Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China.
authors.forename: Shu-Mei
authors.initials: SM
authors.lastname: Ji
authors.forename: Qing-Shan
authors.initials: QS
authors.lastname: Wang
authors.forename: Zhen-Zhong
authors.initials: ZZ
authors.lastname: Fan
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
mesh_terms: D000818:Animals; D004566:Electrodes; D006321:Heart / Q000502:physiology*; D007260:Infusion Pumps; D011898:Ranidae; D014894:Weights and Measures / Q000295:instrumentation*