1. Whole-cell patch recordings were made from antidromically identified sympathetic preganglionic neurons (SPN) of immature rat spinal cord slices. Bath application of nociceptin (0.1-1 μmol/L) suppressed excitatory postsynaptic potentials (EPSP) and hyperpolarized a population of SPN; these effects were naloxone (1 μmol/L) insensitive. 2. Nociceptin suppressed the amplitude of EPSP without causing a concomitant change in glutamate-induced depolarizations, suggesting a presynaptic inhibitory action. 3. Analysis of current-voltage relationships showed that nociceptin hyperpolarized SPN by increasing an inwardly rectifying K+ current. 4. Intrathecal injection of nociceptin (3, 10 and 30 nmol) to urethane-anaesthetized rats dose-dependently reduced the mean arterial pressure and heart rate; these effects were not prevented by prior intravenous injection of naloxone (1 mg/kg). 5. Results from our in vitro and in vivo experiments suggest that nociceptin suppresses spinal sympathetic outflow either by attenuating excitatory synaptic responses or hyperpolarizing SPN.
|頁（從 - 到）||233-237|
|期刊||Clinical and Experimental Pharmacology and Physiology|
|出版狀態||已發佈 - 2002|
ASJC Scopus subject areas
- Pharmacology (medical)
- Pharmacology, Toxicology and Pharmaceutics(all)
Brailoiu, G. C., Lai, C. C., Chen, C. T., Hwang, L. L., Lin, H. H., & Dun, N. J. (2002). Sympathoinhibitory action of nociceptin in the rat spinal cord. Clinical and Experimental Pharmacology and Physiology, 29(3), 233-237. https://doi.org/10.1046/j.1440-1681.2002.03635.x