Myocardial beta-adrenoceptor Function after brain death

对儿茶酚胺反应不佳的移植后心脏功能障碍可能部分与用于脑死亡（BD）供体维持的外源性儿茶酚胺有关。在这项使用犬颅内高压 BD 模型的实验研究中，研究了心肌 β-肾上腺素能受体 (BAR) 的变化。为了维持 BD 后平均动脉压高于 60 mmHg，使用大量晶体液输注（第一组）或 0.4 - 1.3 ug/kg/min 肾上腺素（EPI，第二组）。 DD 3小时（I-3hr，II-3hr）或6小时（I-6hr，II-6hr）后，测量血液EPI水平和心肌BAR（^ 125 I-碘氰吲哚结合）。组n EPI水平BAR密度BAR亲和力。（ng/ml）（fmol/mq）（PM）对照4 0.12±0.05 68.9<正负>6.6 17.9<正负>0.04 64.7<正负>5.8 18.4<正负>6.6 17.9<正负>6.1 18.1<正负II-3小时 4 N.D. 72.3<正负>6.1 18.1<正负II-3小时 4 4.93<plus-minus>0.67 59.2<plus-minus>5.9 19.0<plus-minII-6hr 4 7.04<plus-minus>0.83* 41.0<plus-minus>5.0# 18.6<plus-min(* : p<0.05 vs II-3h, # : P<0.05 vs other)结果表明心肌在脑死亡供体中使用高剂量儿茶酚胺后，BAR 密度可能会降低，这可能是心脏移植中供体心脏功能的部分原因。

Post-transplant cardiac dysfunction with poor response to catecholamine may partly relate to the exogenous catecholamine used for brain-dead (BD) donor maintenance. In this experimental study using canine BD model of intracranial hypertension, alterations in myocardial beta-adrenergic receptor (BAR) were investigated. To maintain the mean arterial pressure higher than 60 mmhg after BD massive crystalloid fluid infusion (Group I) or 0.4 - 1.3 ug/kg/min of epinephrine (EPI, Group II) were used. After 3 hour (I-3hr, II-3hr) or 6 hour (I-6hr, II-6hr) of DD, blood EPI level and myocardial BAR(^<125>I-iodocyanopindlol binding) were measured.group n EPI level BAR density BAR affinity.(ng/ml) (fmol/mq) (PM)control 4 0.12<plus-minus>0.05 68.9<plus-minus>6.6 17.9<plus-minI-3hr 4 0.09<plus-minus>0.04 64.7<plus-minus>5.8 18.4<plus-minI-6hr 4 N. D. 72.3<plus-minus>6.1 18.1<plus-minusII-3hr 4 4.93<plus-minus>0.67 59.2<plus-minus>5.9 19.0<plus-minII-6hr 4 7.04<plus-minus>0.83* 41.0<plus-minus>5.0# 18.6<plus-min(* : p<0.05 vs II-3h, # : P<0.05 vs others)The result suggests that myocardial BAR density may reduce after use of high dose catecholamine in brain-dead donor and this might be partly responsible for donor heart function in heart transplantation.