Simson P E, Cierpial M A, Heyneman L E, Weiss J M
Department of Psychiatry, Duke University Medical Center, Durham, NC 27710.
Neurosci Lett. 1988 Jul 8;89(3):361-6. doi: 10.1016/0304-3940(88)90553-8.
This study assessed the effects of pertussis toxin, which is known to inactivate G proteins and therefore to block receptors linked to G proteins, on electrophysiological activity of the locus coeruleus in vivo. Pertussis toxin was injected into the lateral cerebral ventricle of rats, and locus coeruleus activity was then recorded. Compared to vehicle-injected control animals, pretreatment with pertussis toxin markedly increased the spontaneous firing rate of locus coeruleus neurons. In addition, the alpha 2-antagonist idazoxan was no longer able to augment either spontaneous or evoked locus coeruleus activity after pretreatment with pertussis toxin. Finally, pretreatment with pertussis toxin made locus coeruleus neurons resistant to inhibition by the alpha 2-agonist clonidine. These results are consistent with the view that pertussis toxin blocks alpha 2-receptors, receptors linked to G proteins, in vivo.
本研究评估了已知能使G蛋白失活并因此阻断与G蛋白相连受体的百日咳毒素对体内蓝斑电生理活动的影响。将百日咳毒素注入大鼠侧脑室，然后记录蓝斑活动。与注射赋形剂的对照动物相比，用百日咳毒素预处理显著提高了蓝斑神经元的自发放电率。此外，在用百日咳毒素预处理后，α2拮抗剂咪唑克生不再能够增强蓝斑的自发或诱发活动。最后，用百日咳毒素预处理使蓝斑神经元对α2激动剂可乐定的抑制产生抗性。这些结果与百日咳毒素在体内阻断α2受体（与G蛋白相连的受体）的观点一致。
