Puig M M, Turndorf H, Warner W
Department of Anesthesiology, New York University Medical Center, New York 10016.
Anesthesiology. 1990 Apr;72(4):699-703. doi: 10.1097/00000542-199004000-00020.
The effects of pertussis toxin on the actions of morphine and halothane in the guinea pig ileum are described. Both morphine and halothane produce a dose-related inhibition of electrically induced muscle contraction. The IC50 of morphine was unchanged by the toxin (2.1 and 2.2 X 10(-7) M in control and toxin-pretreated animals). However, the IC50 of halothane was increased from 2.1 to an extrapolated value of 9.1 vol/vol% by pertussis toxin. At high levels of inhibition the interaction between morphine and halothane was synergistic and was converted to additive in the presence of the toxin. These results demonstrate that in the myenteric longitudinal muscle preparation the effects of halothane, but not those of morphine, are mediated by the substrate for pertussis toxin, possibly a Gi membrane protein. The present study provides significant evidence that the effects of halothane on neuronal tissue are dependent upon an interaction with a specific membrane protein.
本文描述了百日咳毒素对豚鼠回肠中吗啡和氟烷作用的影响。吗啡和氟烷均产生与剂量相关的电诱导肌肉收缩抑制作用。毒素未改变吗啡的半数抑制浓度（IC50）（对照动物和毒素预处理动物分别为2.1和2.2×10⁻⁷M）。然而，百日咳毒素使氟烷的IC50从2.1增加到外推值9.1体积/体积%。在高抑制水平时，吗啡和氟烷之间的相互作用是协同的，在毒素存在下转变为相加作用。这些结果表明，在肠肌层纵肌制备中，氟烷的作用而非吗啡的作用是由百日咳毒素的底物介导的，可能是一种Gi膜蛋白。本研究提供了重要证据，表明氟烷对神经元组织的作用取决于与特定膜蛋白的相互作用。
