Franciosa J A, Freis E D
Clin Pharmacol Ther. 1975 Aug;18(2):158-64. doi: 10.1002/cpt1975182158.
Data published by this laboratory indicated that the beta adrenergic blocking drugs timolol and propranolol exerted equivalent beta blocking and antihypertensive actions in patients with mild essential hypertension, but that whereas cardiac output fell acutely with both drugs, it returned to normal after 5 wk of treatment with timolol, but remained depressed after propranolol. This preliminary observation needed further confirmation in a larger series of patients. In this study, 11 patients with initial diastolic blood pressures between 90 and 125 mm Hg were given timolol for 5 wk. Hemodynamic measurements were made before and at the end of treatment. Mean heart rate fell from 76.8 to 64.3 bpm (p less than 0.001), and blood pressure was reduced from 179.4/99 mm Hg to 167.4/93.3 mm Hg (less than 0.02). Cardiac output averaged 6.29 L/min before timolol, and fell to 5.95 L/min (NS) after treatment. Stroke volume increased significantly, while total peripheral resistance was unchanged. These results confirm our earlier observations that timolol is an effective beta adrenergic blocking drug with antihypertensive action that does not reduce cardiac output significantly when given chronically. This drug merits further evaluation in other cardiovascular disorders since it may have advantages over other beta adrenergic blocking drugs.
本实验室发表的数据表明，β肾上腺素能阻滞剂噻吗洛尔和普萘洛尔在轻度原发性高血压患者中具有同等的β受体阻滞和降压作用，但两种药物均可使心输出量急性下降，噻吗洛尔治疗5周后心输出量恢复正常，而普萘洛尔治疗后心输出量仍处于较低水平。这一初步观察结果需要在更多患者中进一步证实。在本研究中，11例初始舒张压在90至125mmHg之间的患者接受噻吗洛尔治疗5周。在治疗前和治疗结束时进行血流动力学测量。平均心率从76.8次/分钟降至64.3次/分钟（p<0.001），血压从179.4/99mmHg降至167.4/93.3mmHg（<0.02）。噻吗洛尔治疗前心输出量平均为6.29L/分钟，治疗后降至5.95L/分钟（无显著性差异）。每搏输出量显著增加，而总外周阻力不变。这些结果证实了我们早期的观察结果，即噻吗洛尔是一种有效的具有降压作用的β肾上腺素能阻滞剂，长期给药时不会显著降低心输出量。由于该药可能比其他β肾上腺素能阻滞剂具有优势，因此值得在其他心血管疾病中进一步评估。
