Tabata H, Holloway H, Fredericks W R, French A W, Rapoport S I
Brain. 1986 Aug;109 ( Pt 4):771-84. doi: 10.1093/brain/109.4.771.
Regional cerebral blood flow (rCBF) was measured in 35 brain regions of awake beagles of different ages, by infusing 14C-iodoantipyrine intravenously. Between 1-3 and 6-12 yrs of age, rCBF was reduced significantly (P less than 0.01) in only 6 of the 35 regions, by 16 to 25%, and mean weighted CBF was not significantly altered. At 14-15 yrs, rCBF was reduced significantly by 25 to 50% in 13 of 28 grey matter regions examined, but in no white matter region, as compared with rCBF at 1-3 yrs of age, and mean weighted CBF was reduced by 30% (P less than 0.01). The course of rCBF during ageing of the beagle corresponded to the reported course of the regional cerebral metabolic rate for glucose. The results demonstrate that cerebral functional activity in most brain regions is constant during much of the adult life of the beagle, and that coupling between blood flow and metabolism also is constant. Compensatory morphological and neurochemical mechanisms may account for this homeostasis of CBF. In extreme senescence, generalized reductions in rCBF are found, and probably reflect reduced sensory input to the brain as well as systemic disease.
通过静脉注射14C-碘安替比林，测量了不同年龄清醒比格犬35个脑区的局部脑血流量（rCBF）。在1至3岁和6至12岁之间，35个区域中只有6个区域的rCBF显著降低（P<0.01），降低了16%至25%，平均加权CBF没有显著变化。在14至15岁时，与1至3岁时的rCBF相比，在所检查的28个灰质区域中的13个区域，rCBF显著降低了25%至50%，但白质区域未出现这种情况，平均加权CBF降低了30%（P<0.01）。比格犬衰老过程中rCBF的变化过程与报道的局部脑葡萄糖代谢率的变化过程一致。结果表明，在比格犬成年后的大部分时间里，大多数脑区的脑功能活动是恒定的，并且血流与代谢之间的耦合也是恒定的。代偿性形态学和神经化学机制可能解释了CBF的这种稳态。在极度衰老时，会出现rCBF的普遍降低，这可能反映了大脑感觉输入的减少以及全身性疾病。
