Department of Anaesthesiology and Intensive Care Medicine, University of Cologne, Kerpener Straße 62, 50937 Köln, Germany. andreas.schneider @uk-koeln.de
Resuscitation. 2012 Feb;83(2):232-7. doi: 10.1016/j.resuscitation.2011.07.023. Epub 2011 Jul 29.
Therapeutic hypothermia improves outcome after cardiac arrest. Dopamine D(2) agonists and serotonin 5-HT(1A) agonists lower body temperature by decreasing the set-point. We investigated the effect of these drugs on temperature and cerebral recovery of rats after cardiac arrest.
Male Wistar-Han rats were subjected to 6 min of cardiac arrest due to ventricular fibrillation. Following restoration of circulation, 1mg quinpirole, 1mg 8-OH-DPAT or vehicle were injected subcutaneously. Body temperature was monitored for 48 h. One additional group was kept normothermic. Animals were neurologically tested by a tape removal test. After 7 days, histology of hippocampal CA-1 sector was analysed with Nissl and TUNEL staining.
Rats became spontaneously hypothermic after cardiac arrest. Induction of hypothermia was facilitated by both quinpirole (-0.033 ± 0.008°C/min) and 8-OH-DPAT (-0.029 ± 0.010°C/min) when compared to vehicle (-0.020 ± 0.005°C/min). Total 'dose' of hypothermia (area under the curve) was not different. All animals showed a neurological deficit, which improved with time; after 7 days, test results of the normothermic group (30 [11-88]s) still tended to be worse than those of the hypothermic groups (vehicle 8 [6-14]s, quinpirole 9 [4-17]s, 8-OH-DPAT 10 [8-22]s). There were no clear differences in Nissl or TUNEL histology after 7 days.
Both quinpirole and 8-OH-DPAT led to faster induction of hypothermia. However, the outcome was not different from spontaneous hypothermia, probably because the total 'dose' of hypothermia was not influenced.
心脏骤停后，治疗性低温可改善预后。多巴胺 D2 激动剂和 5-羟色胺 5-HT1A 激动剂通过降低设定点来降低体温。我们研究了这些药物对心脏骤停后大鼠体温和大脑恢复的影响。
雄性 Wistar-Han 大鼠因心室颤动而发生 6 分钟的心脏骤停。循环恢复后，皮下注射 1mg 喹吡罗、1mg 8-OH-DPAT 或载体。监测体温 48 小时。另外一组保持正常体温。通过胶带去除试验对动物进行神经学测试。7 天后，用尼氏染色和 TUNEL 染色分析海马 CA-1 区的组织学。
大鼠心脏骤停后自发出现体温过低。与载体（-0.020 ± 0.005°C/min）相比，喹吡罗（-0.033 ± 0.008°C/min）和 8-OH-DPAT（-0.029 ± 0.010°C/min）诱导体温过低更容易。低温的总“剂量”（曲线下面积）没有差异。所有动物均出现神经功能缺损，随着时间的推移而改善；7 天后，正常体温组（30 [11-88]s）的测试结果仍倾向于比低温组（载体 8 [6-14]s，喹吡罗 9 [4-17]s，8-OH-DPAT 10 [8-22]s）差。7 天后尼氏染色或 TUNEL 组织学无明显差异。
喹吡罗和 8-OH-DPAT 均导致体温更快下降。然而，结果与自发性低温无差异，可能是因为低温的总“剂量”没有受到影响。
