Clarke R W, Matthews B
Brain Res. 1985 Feb 18;327(1-2):105-11. doi: 10.1016/0006-8993(85)91504-5.
Previous studies indicate that the threshold of the jaw opening reflex (JOR) evoked by tooth-pulp stimulation is much lower in cats subjected to minimal surgical trauma and a short period of anaesthesia than in animals prepared for stereotaxic recording from the brainstem. Experiments have been carried out to determine whether the higher JOR thresholds observed in the latter group of cats could be attributed to the duration of the anaesthesia or the greater surgical trauma to which they were subjected. The effects on the JOR evoked by tooth-pulp stimulation of brief episodes of noxious and high intensity electrical stimulation of other tissues have been studied in anaesthetized cats. In lightly anaesthetized, control animals, the reflex threshold was usually below 100 microA, 0.1 ms and maintained anaesthesia did not affect this. Alphaxalone/alphadolone, methohexitone and alpha-chloralose produced similar results. Noxious or high intensity electrical stimuli applied to a paw, a pinna or the scalp caused either no change or a decrease in the JOR threshold of cats lightly anaesthetized with alphaxalone/alphadolone. With deeper anaesthesia, these same conditioning stimuli caused a maintained increase in JOR threshold which could be reversed by decreasing the anaesthetic dose. The results suggest that the high threshold of the JOR observed in earlier experiments was not due to anaesthesia but may have been caused by trauma.
先前的研究表明，与为从脑干进行立体定位记录而制备的动物相比，遭受最小手术创伤和短时间麻醉的猫，牙髓刺激诱发的下颌开口反射（JOR）阈值要低得多。已经进行了实验，以确定在后者这组猫中观察到的较高JOR阈值是否可归因于麻醉持续时间或它们所遭受的更大手术创伤。在麻醉猫中，研究了对其他组织进行短暂的有害和高强度电刺激对牙髓刺激诱发的JOR的影响。在轻度麻醉的对照动物中，反射阈值通常低于100微安、0.1毫秒，持续麻醉对此没有影响。阿法沙龙/阿法多龙、美索比妥和α-氯醛糖产生了类似的结果。对用阿法沙龙/阿法多龙轻度麻醉的猫，施加于爪子、耳廓或头皮的有害或高强度电刺激，要么使JOR阈值无变化，要么使其降低。在更深麻醉时，这些相同的条件刺激导致JOR阈值持续升高，降低麻醉剂量可使其逆转。结果表明，早期实验中观察到的JOR高阈值不是由于麻醉，而是可能由创伤引起的。
