Monti F, Dawodu A A, Giglio V, Lanti M, del Monte F, Sugimoto S, Terracciano C M, Schiariti M, Puddu P E, Campa P P
II Cattedra di Cardiologia, Istituto di Chirurgia del Cuore e Grossi Vasi, Università degli Studi La Sapienza, Roma.
Cardiologia. 1992 Sep;37(9):635-9.
The study was aimed at comparing the effects of dobutamine (dob) and dopamine (dop) on isotonic contraction and rhythmicity of isolated guinea-pig papillary muscles (in oxygenated Tyrode at 37 degrees C), by taking into account: 1) the rate of stimulation (50% above the diastolic threshold) at 5 fixed periods: (RR: 1600, 1200, 1000, 800 and 400 ms); 2) 7 log concentrations (logC) of the index amine (from 10(-9) to 10(-3) M). To this end, a dose-relation protocol which explored the effects of all 5 RR and 7 logC was designed and 15 adult female Guinea-pigs (250 to 350 g) were randomized to either the dob (n = 8) or the dop (n = 7) arm. This enabled a total of 525 sets of data to be analyzed: in 38 sets (7.2%) premature contractions (CP) were coded. CP were sustained (freq: > 3) in 25 of these latter 38 sets (4.8%). Compared to the basal state, the amplitude (AMP%) and the log of percent amplitude (logAMP%) and time to peak (TP%) changes of the isotonic (Gould transducer) twitch were calculated along with the log of this latter variable (logTP%). AMP%, log AMP%, TP% and logTP% were linearly correlated with logC at all RR. In the range 1600-400 RR, for both amines, significant linear correlations (magnitude of 0.15 > r < magnitude of 0.70, 0.001 > p < 0.022) were seen for plots of AMP%, logAMP% and TP%:steeper correlations were observed for dop. This was confirmed in multivariate analysis (BMDP-9R) whereby AMP%, logAMP%, TP%, logTP%, CP, and freqCP were dependent variables and coded variables were included to either define the type of treatment (dop versus dob) or logC. In these analyses, logC (t > 11) and dop (t > magnitude of 3) might be used to explain (0.28 > r2 < 0.42, 0.00001 > p < 0.0025) AMP% and logAMP%, meaning that a different inotropic (isotonic) efficacy exists between these 2 amines, at all logC. On the other hand, when CP and freqCP were coded, explanatory variables were AMP% and logAMP% (4.86 > t < 6.95, 0.06 > r2 < 0.09, p < 0.00001), but not the variable used to code the type of treatment (dob versus dop).(ABSTRACT TRUNCATED AT 400 WORDS)
本研究旨在比较多巴酚丁胺（dob）和多巴胺（dop）对离体豚鼠乳头肌（在37℃充氧的台氏液中）等张收缩和节律性的影响，研究时考虑了：1）在5个固定周期（RR：1600、1200、1000、800和400毫秒）的刺激频率（高于舒张阈值50%）；2）指标胺的7个对数浓度（logC）（从10⁻⁹到10⁻³M）。为此，设计了一个剂量关系方案，探讨所有5种RR和7种logC的影响，并将15只成年雌性豚鼠（250至350克）随机分为dob组（n = 8）或dop组（n = 7）。这使得总共525组数据得以分析：在38组（7.2%）中记录到过早收缩（CP）。在这38组中的25组（4.8%）中CP持续存在（频率：> 3）。与基础状态相比，计算了等张（古尔德传感器）收缩的幅度（AMP%）、幅度百分比的对数（logAMP%）和达到峰值的时间（TP%）变化以及后一变量的对数（logTP%）。在所有RR下，AMP%、logAMP%、TP%和logTP%与logC呈线性相关。在1600 - 400 RR范围内，对于两种胺，AMP%、logAMP%和TP%的图均显示出显著的线性相关性（0.15 > r < 0.70，0.001 > p < 0.022）：dop的相关性更陡峭。这在多变量分析（BMDP - 9R）中得到证实，其中AMP%、logAMP%、TP%、logTP%、CP和freqCP为因变量，编码变量包括用于定义治疗类型（dop与dob）或logC。在这些分析中，logC（t > 11）和dop（t > 3）可用于解释（0.28 > r² < 0.42，0.00001 > p < 0.0025）AMP%和logAMP%，这意味着在所有logC下，这两种胺之间存在不同的变力（等张）效能。另一方面，当对CP和freqCP进行编码时，解释变量为AMP%和logAMP%（4.86 > t < 6.95，0.06 > r² < 0.09，p < 0.00001），但不是用于编码治疗类型的变量（dob与dop）。（摘要截断于400字）
