Broadley K J
Arch Int Pharmacodyn Ther. 1976 Apr;220(2):189-204.
The effects of various experimental variables upon the optimum temperatures for positive inotropic and chronotropic responses to isoprenaline in isolated cardiac preparations were examined. Perfusion rate and animal (heart) size affected the satisfactory determination of rate and tension optima of guinea-pig and rabbit perfused hearts. Isolated spontaneous atria were assumed to have the same temperature optima as perfused hearts and these were independent of the animal size/age. Paced atria, in which spontaneous rate changes were absent, revealed a sharper tension optimum at an unaltered temperature. The inotropic optimum in all preparations varied with the method of expressing the response; however, since the increase tension remained independent of resting developed tension in pacing experiments, this measure was adopted. The resulting inotropic and chronotropic optima, having minimized these variables, were 25 and 35, and 30 and 37.5 degrees C for guinea-pigs and rabbits respectively. This confirms the separation of these responses by temperature.
研究了各种实验变量对离体心脏制剂中异丙肾上腺素正性肌力和变时性反应最佳温度的影响。灌注速率和动物（心脏）大小影响豚鼠和兔灌注心脏速率和张力最佳值的满意测定。假定离体自发心房与灌注心脏具有相同的温度最佳值，且这些值与动物大小/年龄无关。在无自发速率变化的起搏心房中，在未改变的温度下显示出更明显的张力最佳值。所有制剂中的肌力最佳值随反应表达方法而变化；然而，由于在起搏实验中张力增加与静息时产生的张力无关，因此采用了该测量方法。在最小化这些变量后，豚鼠和兔的肌力和变时性最佳温度分别为25和35摄氏度以及30和37.5摄氏度。这证实了这些反应在温度上的分离。
