Douglas R M, Schmitt B M, Xia Y, Bevensee M O, Biemesderfer D, Boron W F, Haddad G G
Department of Pediatrics, Section of Respiratory Medicine, Yale University School of Medicine, New Haven, CT 06520, USA.
Neuroscience. 2001;102(1):217-28. doi: 10.1016/s0306-4522(00)00473-5.
We used western blotting to examine the developmental profiles (at embryonic day 16 and postnatal days 1, 13, 23, 33 and 105) of protein expression for three sodium-hydrogen exchanger isoforms (1, 2 and 4) and for a sodium-bicarbonate co-transporter in three CNS regions (cortex, cerebellum and brainstem-diencephalon). In microsomal preparations, sodium-hydrogen exchanger isoform 1 and sodium-bicarbonate co-transporter protein expression in the CNS increases gradually from embryonic day 16 (25-40% of the adult level) to postnatal day 105. In contrast, sodium-hydrogen exchanger isoform 2 and 4 expression reaches a maximum (three to 20 times the adult level) at around three to four weeks of age. There is significant regional heterogeneity in the expression of sodium-hydrogen exchanger and sodium-bicarbonate co-transporter proteins in the rat CNS. Sodium-hydrogen exchanger isoform 1 was highly expressed in the brainstem-diencephalon, whereas the sodium-bicarbonate co-transporter was robustly expressed in the cerebellum and brainstem-diencephalon. These data indicate that the expression of sodium-hydrogen exchanger and sodium-bicarbonate co-transporter proteins varies as a function of both development and specific brain region.
我们采用蛋白质印迹法检测了三种钠氢交换体亚型（1、2和4）以及一种钠-碳酸氢根协同转运体在三个中枢神经系统区域（皮层、小脑和脑干-间脑）在胚胎期第16天以及出生后第1、13、23、33和105天的蛋白质表达发育情况。在微粒体制剂中，中枢神经系统中钠氢交换体亚型1和钠-碳酸氢根协同转运体的蛋白质表达从胚胎期第16天（达到成年水平的25%-40%）到出生后第105天逐渐增加。相比之下，钠氢交换体亚型2和4的表达在大约3至4周龄时达到峰值（是成年水平的3至20倍）。大鼠中枢神经系统中钠氢交换体和钠-碳酸氢根协同转运体蛋白的表达存在显著的区域异质性。钠氢交换体亚型1在脑干-间脑高度表达，而钠-碳酸氢根协同转运体在小脑和脑干-间脑强烈表达。这些数据表明，钠氢交换体和钠-碳酸氢根协同转运体蛋白的表达随发育阶段和特定脑区而变化。
