Hynie S, Samánek M, Caisedo M, Roznová L, Hucín B, Vislocký I
Farmakologický ústav 1. LF UK, Praha.
Cas Lek Cesk. 1993 Aug 23;132(16):484-8.
Seventeen children with tetralogy of Fallot undergoing cardiac surgery were investigated for alteration in myocardial beta-adrenergic receptors (BAR) in dependence on the previous chronic administration with the beta-adrenergic blocker metipranolol. Binding parameters, Bmax (maximal binding capacity) and Kd (dissociation constant), in right ventricular tissue were assessed in direct saturation binding studies using 125I-pindolol. It can be concluded that a) chronic administration of metipranolol to nine patients in usual doses did not change either Bmax or Kd of BAR in the samples of right ventricle, and b) twelve hours interval between last dose of metipranolol and removal of tissue samples is sufficiently long to enable normalization of possible changes in the sensitivity of BAR. This finding is supported by the pot-operative course and the response to dopamine which did not differ in patients treated and untreated with metipranolol in the preoperative period. Thus, our results suggest that there is no apprehension of chronic application of beta-blockers in patients with tetralogy of Fallot which would negatively influence the response to dopamine during the operation and in the postoperative period.
对17名接受心脏手术的法洛四联症患儿进行了研究，以探讨心肌β-肾上腺素能受体（BAR）的变化与先前长期使用β-肾上腺素能阻滞剂美替洛尔之间的关系。在使用125I-吲哚洛尔的直接饱和结合研究中，评估了右心室组织中的结合参数Bmax（最大结合容量）和Kd（解离常数）。可以得出以下结论：a）对9名患者按常规剂量长期使用美替洛尔，并未改变右心室样本中BAR的Bmax或Kd；b）在最后一剂美替洛尔与取出组织样本之间间隔12小时足够长，足以使BAR敏感性的可能变化恢复正常。术前接受和未接受美替洛尔治疗的患者术后病程及对多巴胺的反应并无差异，这一发现得到了支持。因此，我们的结果表明，对于法洛四联症患者长期应用β受体阻滞剂无需担心，这不会对手术期间及术后对多巴胺的反应产生负面影响。
