Smith D J, Westfall D P, Adams J D
Neuropharmacology. 1982 Jul;21(7):605-11. doi: 10.1016/0028-3908(82)90001-6.
The anesthetic agent ketamine was studied for its ability to interact with opiate receptors in the longitudinal smooth muscle-myenteric plexus preparation of the guinea-pig ileum. The drug was found to possess agonistic, but not antagonistic, activity on opiate receptors. Naloxone antagonized the effect of ketamine although to a lesser degree than the antagonism exhibited toward morphine. In addition to the opiate action, ketamine also produced a depression of the contractile responses of the ileal smooth muscle to acetylcholine and histamine. The concentrations of ketamine that produced this non-specific depression were generally higher than those needed to demonstrate the opiate effect. However, some overlap in the concentration ranges for the two actions were observed. Although the nature of the opiate action of ketamine suggested that it interacts with opiate receptors or sub-types of these differently than does morphine, the non-specific action of the drug on the ileal smooth muscle precluded a definitive analysis of differences in the opiate receptor preferences of the drug.
研究了麻醉剂氯胺酮与豚鼠回肠纵行平滑肌 - 肠肌丛制剂中阿片受体相互作用的能力。发现该药物对阿片受体具有激动活性，但不具有拮抗活性。纳洛酮拮抗氯胺酮的作用，尽管其拮抗程度低于对吗啡的拮抗程度。除了阿片样作用外，氯胺酮还使回肠平滑肌对乙酰胆碱和组胺的收缩反应受到抑制。产生这种非特异性抑制作用的氯胺酮浓度通常高于显示阿片样作用所需的浓度。然而，观察到两种作用的浓度范围存在一些重叠。尽管氯胺酮的阿片样作用性质表明它与阿片受体或其亚型的相互作用方式与吗啡不同，但该药物对回肠平滑肌的非特异性作用妨碍了对该药物阿片受体偏好差异的明确分析。
