The effects of acetylcholine in the heart‐lung preparation including the production of auricular fibrillation
The effects of acetylcholine in the heart‐lung preparation including the production of auricular fibrillation
复制标题
DOI：
10.1113/jphysiol.1955.sp005306
复制
发表时间：
1955-05
期刊：
影响因子：
--
通讯作者：
J. Burn;E. Williams;J. Walker
中科院分区：
文献类型：
--
作者：
J. Burn;E. Williams;J. Walker
方法采用Knowlton & Starling（1912）的制备方法。每次实验使用两只狗。第一组用乙醚麻醉，颈动脉采血。第二个人也用乙醚麻醉，并抽出一些血液加入第一个人的血液中，形成实验的储存库。然后，在氯氯蔗糖（0.07 g/kg）的作用下，对第二只狗的心肺进行制备，但是，由于实验中使用的储血只暴露于乙醚中（很快在空气中被除去），因此麻醉剂的最终浓度可能少于70 mg /l氯氯蔗糖。血。静脉储液器浸泡在恒温浴中，有一个溢出管，超过这个溢出管，血液水平就不能上升。溢出管将多余的血液引导到位于第一个容器下方的第二个容器中；然后通过戴尔-舒斯特（1928）泵返回顶部水库。这样就保证了恒定的静脉压。用肝素（Boots） 5000单位/升防止血液凝固。在每次实验中，每隔5分钟记录一次静脉插管内的温度，并调节泡澡的温度以保持恒定。心电图（ecg）是在Cossor 1314型机器上记录的，该机器使用开尔文-休斯（Kelvin-Hughes）笔直接在Teledeltos纸上书写。在去除一些皮肤后，将导线连接到左右前腿和左后腿上。耳廓是通过一个相当传统的方波刺激器在任何需要的频率下跳动的。恒流脉冲持续时间为0.9 msec，强度为1ma。刺激器有两个独立的通道，每个通道与频率、延迟、持续时间和强度有关。它
METHODS The preparation was made by the method described by Knowlton & Starling (1912). Two dogs were used for each experiment. Thefirst was anaesthetized with ether and its blood was collected from the carotid artery. The second was also anaesthetized with ether, and some blood was withdrawn and added to the blood of the first, to form a reservoir for the experiment. The preparation of the heart-lung in the second dog then proceeded under chloralose (0.07 g/kg), but, since the reservoir blood used during the experiment had been exposed only to ether (which was soon removed in the expired air), the final concentration of anaesthetic consisted of probably less than 70 mg chloralose/l. blood. The venous reservoir, which was immersed in a constant temperature bath, contained an overflow tube above which the level of blood could not rise. The overflow tube led the excess blood to a second reservoir placed below the first; it was then returned to the top reservoir by a Dale-Schuster (1928) pump. Thus a constant venous pressure was ensured. The blood was prevented from clotting with heparin (Boots) 5000 units/l. The temperature in the venous cannula was recorded at 5 min intervals throughout each experiment, and the heating of the bath was adjusted to keep it constant.Electrocardiograms (ecg) were taken on a Cossor machine, model 1314, which employs a Kelvin-Hughes pen writing directly on Teledeltos paper. The leads were attached to the right and left forelegs and the left hindleg after removal ofsome skin. The auricles were made to beat at any required frequency by means ofa square-wave stimulator offairly conventional design. Constant current pulses of duration 0 9 msec and strength 1 mA were employed. The stimulator had two independent channels, each variable with respect to frequency, delay, duration and strength. It