Brust P, Zicha J
Department of Cell Biology and Regulation, Karl Marx University, Leipzig, GDR.
Biomed Biochim Acta. 1988;47(12):1013-21.
The transport of L-leucine across the blood-brain barrier was studied in heterozygous (NON-DI) and homozygous (DI) Brattleboro male rats using the carotid bolus injection technique. Furthermore, general hemodynamic parameters and cerebral blood flow were measured. No significant hemodynamic differences were found between DI and NON-DI rats except for a 22% lower cerebral blood flow in the olfactory bulb of DI rats. The maximum velocity of L-leucine transport (Vmax), the half saturation constant (Km) and the nonsaturable transport constant (KD) were estimated in nine brain regions. The Vmax values of NON-DI rats were by 28% to 64% lower than those of DI rats. The calculated regional Km values of NON-Di rats were by 14% to 58% lower. These differences were most pronounced in hippocampus and hypothalamus. The results support the suggestion that endogenous vasopressin may alter the large neutral amino acid transport across the blood-brain barrier.
采用颈动脉团注注射技术，在杂合子（NON-DI）和纯合子（DI）布拉特洛维雄性大鼠中研究了L-亮氨酸跨血脑屏障的转运。此外，还测量了一般血液动力学参数和脑血流量。除了DI大鼠嗅球的脑血流量低22%外，DI和NON-DI大鼠之间未发现明显的血液动力学差异。在九个脑区估计了L-亮氨酸转运的最大速度（Vmax）、半饱和常数（Km）和非饱和转运常数（KD）。NON-DI大鼠的Vmax值比DI大鼠低28%至64%。NON-Di大鼠计算出的区域Km值低14%至58%。这些差异在海马体和下丘脑最为明显。结果支持内源性血管加压素可能改变大中性氨基酸跨血脑屏障转运的观点。
