Manhem P J, Brown W B, Clark S A, Leckie B, Murray G, Otipka N, Robertson J I
MRC Blood Pressure Unit, Western Infirmary, Glasgow, Scotland.
Clin Exp Hypertens A. 1989;11(4):603-17. doi: 10.3109/10641968909035363.
The cardioselective beta-blocker metoprolol was mixed with the diet (6 mg metoprolol/g food) and given to 9 spontaneously hypertensive rats (SHR) for four weeks, while 9 other SHR were given the plain diet only and served as controls. All rats were also given 0.5% drinking saline labeled with isotope 22Na (37 kBq/1) to drink. Measurements of total exchangeable sodium, blood pressure, pulse rate and weight were performed before and repeatedly during treatment. Plasma renin activity was measured at the end of the study. Before treatment exchangeable sodium, blood pressure, pulse rate and weight were no different between the groups. Metoprolol reduced the pulse rate and prevented the usual blood pressure increase in SHR. Both groups gained weight similarly. Exchangeable sodium increased similarly in both groups along with the weight increase. Plasma renin activity was not significantly different in the two groups. Thus, chronic metoprolol treatment of SHR reduced blood pressure and pulse rate in SHR but did not lower plasma renin or cause measurable sodium or fluid retention.
将心脏选择性β受体阻滞剂美托洛尔与饮食混合（6毫克美托洛尔/克食物），给予9只自发性高血压大鼠（SHR），持续四周，而另外9只SHR只给予普通饮食作为对照。所有大鼠还给予含有同位素22Na（37 kBq/1）的0.5%饮用盐水饮用。在治疗前和治疗期间反复进行总可交换钠、血压、脉搏率和体重的测量。在研究结束时测量血浆肾素活性。治疗前，两组之间的可交换钠、血压、脉搏率和体重没有差异。美托洛尔降低了脉搏率，并阻止了SHR中常见的血压升高。两组体重增加相似。随着体重增加，两组的可交换钠同样增加。两组的血浆肾素活性没有显著差异。因此，对SHR进行慢性美托洛尔治疗可降低SHR的血压和脉搏率，但不会降低血浆肾素或导致可测量的钠或液体潴留。
