Meert T F, Noorduin H, Van Craenendonck H, Vermote P, Boersma F P, Janssen P A
Department of Neuropsychopharmacology, Janssen research Foundation, Beerse, Belgium.
Acta Anaesthesiol Belg. 1989;40(4):247-61.
A study was made of the effects of different volumes of injection product, adrenaline, the alpha 2-adrenoceptor-agonist medetomidine and Mycobacterium butyricum on epidural sufentanil in the rat. Increasing the volume of epidural sufentanil, and similarly decreasing the concentration of the injection product, resulted in a potentiation of the analgesic properties of epidural sufentanil without affecting the effects of the drug on the pinna and cornea reflexes and on muscle tonus. An analogue effect was observed if rats were tested for epidural analgesia during a chronic pain phase after inoculation with Mycobacterium butyricum. Adding adrenaline to epidural sufentanil also resulted in an increased analgesia but there was also a minor potentiation of all other behavioural parameters measured. The alpha 2-adrenoceptor-agonist medetomidine, clearly potentiated all behavioural effects induced by epidural sufentanil. As a consequence, there was no gain in specificity for epidural analgesia. Medetomidine, however, clearly reversed the normally observed skeletal muscle rigidity into a muscle hypotonia. Globally, these results thus indicate that manipulations of the volume of injection, the additional treatment with other drugs and the pain state of the animal can alter the activity of epidural sufentanil. Therefore, it might be concluded that the differences in the duration of analgesia observed with epidural sufentanil between human and animal studies can be partially explained in terms of differences between the experimental conditions.
研究了不同体积的注射剂、肾上腺素、α2-肾上腺素能受体激动剂美托咪定和丁酸分枝杆菌对大鼠硬膜外舒芬太尼的影响。增加硬膜外舒芬太尼的体积，同样降低注射剂的浓度，可增强硬膜外舒芬太尼的镇痛特性，而不影响该药物对耳廓和角膜反射以及肌肉张力的作用。如果在接种丁酸分枝杆菌后的慢性疼痛阶段对大鼠进行硬膜外镇痛测试，也会观察到类似的效果。向硬膜外舒芬太尼中添加肾上腺素也会导致镇痛作用增强，但同时所测量的所有其他行为参数也会有轻微增强。α2-肾上腺素能受体激动剂美托咪定明显增强了硬膜外舒芬太尼诱导的所有行为效应。因此，硬膜外镇痛的特异性并未提高。然而，美托咪定明显将通常观察到的骨骼肌强直转变为肌张力减退。总体而言，这些结果表明，注射体积的改变、其他药物的额外治疗以及动物的疼痛状态均可改变硬膜外舒芬太尼的活性。因此，可以得出结论，在人和动物研究中观察到的硬膜外舒芬太尼镇痛持续时间的差异，部分可以用实验条件的差异来解释。
