Crawford R A, Griffiths I R, McCulloch J
J Neurosurg. 1977 Oct;47(4):567-76. doi: 10.3171/jns.1977.47.4.0567.
The effect of intra-arterially administered norepinephrine (NE) upon spinal cord blood flow (SCBF), before and after disruption of the blood-cord barrier was studied in dogs. Barrier disruption was accomplished with an intra-arterial bolus injection of 2.5 M urea. Multiple ligations of branches of the posterior aorta and cannula placements ensured that the urea was directed to the lumbar and sacral segments of the cord. The SCBF was measured by the hydrogen clearance method. Intra-arterial urea by itself had no significant effect on SCBF. The intra-arterial infusion of NE (12 microgram/min and 30 microgram/min) was without overall effect on SCBF. However, if the blood-cord barrier had been previously disrupted with hypertonic urea, both concentrations of NE resulted in large reductions in SCBF. No such reductions in SCBF were seen with blood-cord barrier disruption and NE if the animals had been pre-treated with the alpha-blocker, phenoxybenzamine (1.5 mg/kg). Some aspects of the possible involvement of NE in the pathophysiology of acute spinal injury are discussed.
研究了动脉内注射去甲肾上腺素（NE）对犬脊髓血流（SCBF）的影响，观察了血脊髓屏障破坏前后的情况。通过动脉内推注2.5M尿素来破坏屏障。对主动脉后支进行多次结扎并放置插管，以确保尿素作用于脊髓的腰段和骶段。采用氢清除法测量脊髓血流。动脉内注射尿素本身对脊髓血流无显著影响。动脉内输注NE（12微克/分钟和30微克/分钟）对脊髓血流总体无影响。然而，如果血脊髓屏障先前已被高渗尿素破坏，两种浓度的NE都会导致脊髓血流大幅减少。如果动物预先用α受体阻滞剂酚苄明（1.5毫克/千克）处理，血脊髓屏障破坏加NE时则未见脊髓血流如此减少。讨论了NE可能参与急性脊髓损伤病理生理的某些方面。
