Scremin O U, Holschneider D P, Chen K, Li M G, Shih J C
Department of Physiology, UCLA School of Medicine, Los Angeles, CA, USA.
Brain Res. 1999 Apr 3;824(1):36-44. doi: 10.1016/s0006-8993(99)01167-1.
Cerebral cortical blood flow (CBF) was measured autoradiographically in conscious mice without the monoamine oxidase B (MAOB) gene (KO, n=11) and the corresponding wild-type animals (WILD, n=11). Subgroups of animals of each genotype received a continuous intravenous infusion over 30 min of phenylethylamine (PEA), an endogenous substrate of MAOB, (8 nmol g-1 min-1 in normal saline at a volume rate of 0.11 microl g-1 min-1) or saline at the same volume rate. Maps of relative CBF distribution showed predominance of midline motor and sensory area CBF in KO mice over WILD mice that received saline. PEA enhanced CBF in lateral frontal and piriform cortex in both KO and WILD mice. These changes may reflect a differential activation due to chronic and acute PEA elevations on motor and olfactory function, as well as on the anxiogenic effects of this amine. In addition to its effects on regional CBF distribution, PEA decreased CBF globally in KO mice (range -31% to -41% decrease from control levels) with a lesser effect in WILD mice. It is concluded that MAOB may normally regulate CBF distribution and its response to blood PEA.
采用放射自显影法测量了缺乏单胺氧化酶B（MAOB）基因的清醒小鼠（基因敲除组，KO，n = 11）和相应野生型动物（野生组，WILD，n = 11）的大脑皮质血流量（CBF）。每种基因型的动物亚组接受30分钟的苯乙胺（PEA，MAOB的内源性底物，以0.11微升/克/分钟的体积速率溶于生理盐水中，浓度为8纳摩尔/克/分钟）或相同体积速率的生理盐水的持续静脉输注。相对CBF分布图显示，接受生理盐水的基因敲除小鼠中线运动和感觉区域的CBF高于野生小鼠。PEA增强了基因敲除小鼠和野生小鼠额叶外侧和梨状皮质的CBF。这些变化可能反映了慢性和急性PEA升高对运动和嗅觉功能以及该胺类致焦虑作用的不同激活。除了对局部CBF分布的影响外，PEA使基因敲除小鼠的整体CBF降低（比对照水平降低31%至41%），对野生小鼠的影响较小。得出的结论是，MAOB通常可能调节CBF分布及其对血液中PEA的反应。
