山羊急性应激反应评价及心脏电稳定性研究

【目的】探索山羊急性应激反应定量评价方法，了解急性应激及β肾上腺素能受体阻断剂干预对山羊心脏电稳定性影响。【方法】复合刺激诱发山羊急性应激反应，高效液相色谱法测定血浆肾上腺素、去甲肾上腺素浓度。心尖部双极电极S1S2程序刺激测定室颤阈、心室易损期。【结果】与对照组相比，急性应激组山羊血浆肾上腺素、去甲肾上腺素浓度随刺激时间延长进行性升高，室颤阈明显降低，心室易损期显著增宽。美托洛尔干预组与急性应激组相比，室颤阈显著增加，心室易损期变窄。【结论】山羊复合刺激后呈明显应激，且随时间延长应激反应相应增强，心脏电不稳定性显著增加，β肾上腺素能受体阻断剂干预可部分拮抗其作用。

Evaluation of acute stress and study of cardiac electrical stability of goats

[Objective] To explore quantitative methods for assessing acute stress and the effect of acute stress and β adrenergic receptor antagonist on electrical stability of goat hearts. [Methods] Complex stimuli were used to induce acute stress of goats. Plasma epinephrine and norepinephrine concentration was measured by HPLC（high performance liquid chromatogram, HPLC）. VFT（ventricular fibrillation threshold, VFT） and VVP（ventricular vulnerable period, VVP） were measured by programmed S1S2 stimuli with bipolar electrodes at apex of goat hearts. [ Results] Compared with control group, plasma epinephrine and norepinephrine levels of acute stress goats increased progressively , VFT decreased significantly and VVP broadened remarkably. VFT of metoprolol group increased and VVP narrowed sigrrificantly in contrast to acute stress group. [ Conclusions] Goats with complex stimuli appear stress remarkably, and stressful reaction increases with stimulating time. Electrical unstability of hearts of stressful goats increases significantly. However, β adrenergic receptor antagonist can counteract the effect partially.