Iwai A, Monafo W W, Eliasson S G
Department of Surgery, Washington University School of Medicine, St. Louis, Missouri 63110.
Am J Physiol. 1991 Mar;260(3 Pt 2):H827-31. doi: 10.1152/ajpheart.1991.260.3.H827.
We used [14C]butanol distribution to measure regional spinal cord blood flow (RSCBF) in three groups of pentobarbital-anesthetized rats: 1) normals (n = 16); 2) after bilateral adrenalectomy (n = 18); and 3) after excision of the abdominal sympathetic chains (n = 12). Half of the rats in each group were maintained near normothermia; the remainder were colled to a rectal temperature of 25-27 degrees C. In intact rats, there was a 24-37% increase in RSCBF during hypothermia in the cord region C3-L6 inclusive. Neither operative procedure altered RSCBF during normothermia. In hypothermic adrenalectomized rats, RSCBF was elevated only in the C3-C5 cord segment. After sympathectomy, RSCBF was unchanged during hypothermia. In the cauda equina, flow fell in all hypothermic rats. The hypothermia-associated increases in RSCBF were not related to changes in mean arterial blood pressure. We conclude that adrenalectomy near-totally ablates the hypothermia-associated increase in RSCBF measured in intact rats and that abdominal sympathectomy totally ablates it. This evidence complements morphological evidence for adrenergic innervation of the spinal cord vasculature.
我们采用[14C]丁醇分布法测量三组戊巴比妥麻醉大鼠的脊髓局部血流量（RSCBF）：1）正常大鼠（n = 16）；2）双侧肾上腺切除术后大鼠（n = 18）；3）腹部交感神经链切除术后大鼠（n = 12）。每组一半的大鼠维持在接近正常体温的状态；其余大鼠则将直肠温度降至25 - 27摄氏度。在完整大鼠中，体温过低时，包括C3 - L6节段在内的脊髓区域RSCBF增加24% - 37%。两种手术操作在正常体温时均未改变RSCBF。在体温过低的肾上腺切除大鼠中，RSCBF仅在C3 - C5脊髓节段升高。交感神经切除术后，体温过低时RSCBF无变化。在马尾，所有体温过低的大鼠血流量均下降。体温过低相关的RSCBF增加与平均动脉血压变化无关。我们得出结论，肾上腺切除术几乎完全消除了完整大鼠中测量到的体温过低相关的RSCBF增加，而腹部交感神经切除术则完全消除了这种增加。这一证据补充了脊髓血管系统肾上腺素能神经支配的形态学证据。
