Gerard H, Sensky P L, Broom D M, Perremans S, Geers R
Laboratorium Agrarische Bouwkunde, Katholieke Universiteit Leuven, Heverlee, Belgium.
Vet Res. 1996;27(3):219-26.
Two experiments were carried out using a total of 20 growing pigs of approximately 20 kg in order to investigate the effect of different types of anaesthesia (metomidate versus ketamine) on plasma levels of cortisol and beta-endorphin on the heart rate. The animals were housed individually within a zone of thermal neutrality. Feed and water were available ad libitum. After becoming accustomed to human contact (being approached and touched), a catheter was implanted in the jugular vein, exteriorized in the neck region. This operation was performed under halothane anaesthesia. After recovery, hourly blood samples were taken over a 27 hour period, and cortisol and beta-endorphin concentrations were measured in the sample plasma. After this reference period, half of the animals were anaesthetized with metomidate, the other half with ketamine, and blood samples were taken at regular intervals. During a second experiment the heart rate was monitored after being anaesthetized as described before. An influence of the type of anaesthesia was observed on the plasma concentration of cortisol, but no effect was observed with respect to the beta-endorphin concentration. A fivefold increase of cortisol concentration was observed after injection with ketamine, while a twofold increase was observed after injection with metomidate. This finding suggests a suppressive effect of metomidate on the plasma cortisol levels. A fivefold increase was also observed for the beta-endorphin concentration after injection with either ketamine or metomidate. The increase in the heart rate was related to the awakening activity, which was more difficult after the ketamine injection.
进行了两项实验，共使用20头体重约20千克的生长猪，以研究不同类型麻醉（美托咪酯与氯胺酮）对血浆皮质醇水平、β-内啡肽水平及心率的影响。动物单独饲养在热中性区域内。自由提供饲料和水。在习惯与人接触（被接近和触摸）后，在颈静脉植入一根导管，并在颈部区域引出。此操作在氟烷麻醉下进行。恢复后，在27小时内每小时采集血样，并测定样本血浆中的皮质醇和β-内啡肽浓度。在此参照期后，一半动物用美托咪酯麻醉，另一半用氯胺酮麻醉，并定期采集血样。在第二项实验中，按照之前描述的方法麻醉后监测心率。观察到麻醉类型对血浆皮质醇浓度有影响，但对β-内啡肽浓度未观察到影响。注射氯胺酮后皮质醇浓度增加了五倍，而注射美托咪酯后增加了两倍。这一发现表明美托咪酯对血浆皮质醇水平有抑制作用。注射氯胺酮或美托咪酯后，β-内啡肽浓度也增加了五倍。心率增加与苏醒活动有关，注射氯胺酮后苏醒更困难。
