Meyers R S, Moalli R, Jackson D C, Millard R W
J Exp Zool. 1979 Jun;208(3):423-30. doi: 10.1002/jez.1402080318.
Bidirectional central vascular shunts were measured during diving and breathing in air in unanesthetized bullfrogs by using pulmonary trapping of 38 mu mean diameter radionuclide-labelled microspheres. Six animals studied during diving exhibited a strong overall right-to-left shunting pattern comprised of both a predominant (68% mean) right-to-left shunt and a weak (23%) left-to-right countershunt. Five animals with access to air showed a variety of distribution patterns, including predominant shunts in the left-to-right (1 animal) and right-to-left (1 animal) directions, nearly complete mixing (2 animals) and separation of systemic and pulmonary venous returns (1 animal).
在未麻醉的牛蛙潜水和呼吸空气期间，通过使用平均直径为38微米的放射性核素标记微球的肺捕获法来测量双向中心血管分流。在潜水期间研究的6只动物表现出强烈的总体右向左分流模式，包括主要的（平均68%）右向左分流和较弱的（23%）左向右反向分流。5只能够接触空气的动物表现出多种分布模式，包括左向右（1只动物）和右向左（1只动物）方向的主要分流、几乎完全混合（2只动物）以及体循环和肺静脉回流分离（1只动物）。
