Rorie D K, Hunter L W, Lunn J J
Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota 55905.
Anesthesiology. 1990 Oct;73(4):722-30. doi: 10.1097/00000542-199010000-00019.
Neuropeptide Y (NPY), norepinephrine (NE), and 3,4-dihydroxyphenylglycol (DOPEG), the metabolite of NE that arises intraneuronally, were measured in superfusates before, during, and after nerve stimulation and in extracts of dog pulmonary artery after superfusion and electrical stimulation (ES) at 12, 6, and 1 Hz. NE and DOPEG were quantified by high-pressure liquid chromatography with electrochemical detection; peptides were quantified by radioimmunoassay. The rate of overflow of NPY, NE, and DOPEG into superfusate was measured over time. The overflow of DOPEG into superfusate during basal conditions was 3.0 times that of NE. Efflux of DOPEG and NPY increased during ES; peak effluxes were not reached, however, until after cessation of stimulation. NE efflux peaked during ES. Effluxes of NE, NPY, and DOPEG were frequency-dependent at 12 and 6 Hz; at 1 Hz efflux of only NE was greater than basal. Halothane decreased significantly the rates of NPY and DOPEG efflux during and after 12 Hz ES; DOPEG efflux evoked by 6 Hz stimulation was also decreased by halothane. The percentage of the total tissue content of NPY that overflowed was decreased by halothane. Halothane did not affect the molar ratios of NE:DOPEG or NE:NPY during basal conditions or ES. These studies provide evidence that halothane slows efflux of NPY that is released along with NE from dog pulmonary artery during high frequencies of stimulation. Halothane also reduces the metabolism of NE to DOPEG.
在神经刺激前、刺激期间和刺激后，对细胞外灌流液中的神经肽Y（NPY）、去甲肾上腺素（NE）以及NE的神经元内代谢产物3,4-二羟基苯乙二醇（DOPEG）进行了测定，并在12Hz、6Hz和1Hz的灌流及电刺激（ES）后，对犬肺动脉提取物中的这些物质进行了测定。NE和DOPEG通过高压液相色谱-电化学检测进行定量；肽类通过放射免疫测定进行定量。随时间测量了NPY、NE和DOPEG向细胞外灌流液中的溢出率。基础条件下DOPEG向细胞外灌流液中的溢出量是NE的3.0倍。ES期间DOPEG和NPY的流出增加；然而，直到刺激停止后才达到峰值流出量。NE流出在ES期间达到峰值。在12Hz和6Hz时，NE、NPY和DOPEG的流出呈频率依赖性；在1Hz时，仅NE的流出大于基础值。氟烷显著降低了12Hz ES期间和之后NPY和DOPEG的流出率；氟烷也降低了6Hz刺激引起的DOPEG流出。氟烷降低了溢出的NPY占组织总含量的百分比。氟烷在基础条件或ES期间不影响NE:DOPEG或NE:NPY的摩尔比。这些研究提供了证据，表明氟烷减缓了在高频刺激期间与NE一起从犬肺动脉释放的NPY的流出。氟烷还减少了NE向DOPEG的代谢。
