Saransaari P, Oja S S
Department of Biomedical Sciences, University of Tampere, Finland.
Neurochem Res. 1994 Jan;19(1):77-82. doi: 10.1007/BF00966732.
Taurine is an important modulator of neuronal activity in the immature brain. In kittens, taurine deficiency causes serious dysfunction in the cerebellar and cerebral visual cortex. The processes of taurine transport in vitro were now studied for the first time in different brain areas in developing and adult cats. The uptake of taurine consisted initially of two saturable components, high- and low-affinity, in synaptosomal preparations from the developing cerebral cortex and cerebellum, but the high-affinity uptake component completely disappeared during maturation. The release of both endogenous and preloaded labeled taurine from brain slices measured in a superfusion system was severalfold stimulated with a slow onset by depolarizing K+ (50 mM) concentrations. K+ stimulation released markedly more taurine from the cerebral cortex, cerebellum and brain stem in kittens than in adult cats. The responses were largest in the cerebellum. Both uptake and release of taurine are thus highly efficient in the brain of kittens and may be of significance in view of the vulnerability of cats to taurine deficiency.
牛磺酸是未成熟大脑中神经元活动的重要调节因子。在小猫中，牛磺酸缺乏会导致小脑和大脑视觉皮层严重功能障碍。现在首次在发育中和成年猫的不同脑区研究了牛磺酸的体外转运过程。在发育中的大脑皮层和小脑的突触体制剂中，牛磺酸的摄取最初由两个可饱和成分组成，即高亲和力和低亲和力成分，但高亲和力摄取成分在成熟过程中完全消失。在灌注系统中测量的脑片内源性和预加载标记牛磺酸的释放，在50 mM去极化钾浓度下受到缓慢起效的几倍刺激。钾刺激从小猫的大脑皮层、小脑和脑干释放的牛磺酸明显多于成年猫。小脑的反应最大。因此，牛磺酸在小猫大脑中的摄取和释放都非常高效，鉴于猫对牛磺酸缺乏的易感性，这可能具有重要意义。
