Scholtysik G
J Pharmacol Methods. 1986 Jul;15(4):367-73. doi: 10.1016/0160-5402(86)90015-x.
In rabbit papillary muscles, potentiating paired stimulation was used as a standard positive inotropic intervention. Pairs of depolarizing electrical stimuli were applied, equal in strength and with a coupling interval of the functional refractory period plus 10 msec. After five successive pairs at a basic driving rate of 0.5 Hz, maximum potentiation amounting to a two- to threefold increase in the contraction amplitude was reached. The potentiating paired stimulation was rapid in both onset and reversibility and was reproducible. Potentiating paired stimulation is sparing since internal Ca2+ pools are utilized to increase force. Using potentiating paired stimulation-induced increase in force of contraction as a new reference, the following order of potency of positive inotropic agents was obtained: ouabain greater than DPI 201-106 greater than IBMX greater than APP 201-533. Effects of these drugs on rested-state contractions and frequency-force relationship were also investigated.
在兔乳头肌中，增强配对刺激被用作标准的正性肌力干预措施。施加成对的去极化电刺激，强度相等，耦合间隔为功能性不应期加10毫秒。以0.5 Hz的基本驱动频率连续施加五对刺激后，收缩幅度达到最大增强，增加了两到三倍。增强配对刺激在起效和可逆性方面都很快，并且可重复。增强配对刺激是节省能量的，因为利用了细胞内钙库来增加力量。以增强配对刺激诱导的收缩力增加作为新的参考，得到了以下正性肌力药物的效价顺序：哇巴因大于DPI 201-106大于异丁基甲基黄嘌呤大于APP 201-533。还研究了这些药物对静息状态收缩和频率-力量关系的影响。
