Busija D W, Leffler C W, Pourcyrous M
Department of Physiology and Biophysics, University of Tennessee, Memphis 38163.
Am J Physiol. 1988 Aug;255(2 Pt 2):H343-6. doi: 10.1152/ajpheart.1988.255.2.H343.
We examined effects of hyperthermia on cerebral metabolic rate for oxygen (CMRO2) and cerebral blood flow (CBF) in anesthetized, newborn pigs (2-5 days old). CBF and CMRO2 were measured during normothermia (38 degrees C) and during hyperthermia induced by body heating (42 degrees C). During normothermia, total CBF was 32 +/- 3 ml.min-1.100 g-1 (n = 9), and CMRO2 was 1.34 +/- 0.08 ml O2.100 g-1.min-1 (n = 7). During hyperthermia, total CBF increased by 97 +/- 23% and CMRO2 by 65 +/- 24%. We also examined whether cerebral resistance vessels were responsive under these conditions. During hyperthermia, total CBF was 63 +/- 6 ml.min-1.100 g-1, and CMRO2 was 2.13 +/- 0.27 ml O2.100 g-1.min-1. During sustained hyperthermia, intravenous injection of 5 mg/kg of indomethacin decreased total CBF by 45 +/- 7% (n = 9), and CMRO2 fell by 55 +/- 10% (n = 5). We conclude that 1) hyperthermia increases CBF and CMRO2, and 2) the dilated cerebrovascular bed during hyperthermia still is responsive to a constrictor stimulus.
我们研究了高温对麻醉状态下新生猪（2 - 5日龄）脑氧代谢率（CMRO2）和脑血流量（CBF）的影响。在正常体温（38摄氏度）以及通过身体加热诱导的高温（42摄氏度）期间测量CBF和CMRO2。在正常体温期间，总CBF为32±3 ml·min⁻¹·100 g⁻¹（n = 9），CMRO2为1.34±0.08 ml O₂·100 g⁻¹·min⁻¹（n = 7）。在高温期间，总CBF增加了97±23%，CMRO2增加了65±24%。我们还研究了在这些条件下脑阻力血管是否有反应。在高温期间，总CBF为63±6 ml·min⁻¹·100 g⁻¹，CMRO2为2.13±0.27 ml O₂·100 g⁻¹·min⁻¹。在持续高温期间，静脉注射5 mg/kg的吲哚美辛使总CBF降低了45±7%（n = 9），CMRO2降低了55±10%（n = 5）。我们得出结论：1）高温会增加CBF和CMRO2；2）高温期间扩张的脑血管床仍然对收缩刺激有反应。
