Acidosis‐Induced Enhanced Activity of the Na‐K Exchange Pump in the In Vivo Choroid Plexus: An Ontogenetic Analysis of Possible Role in Cerebrospinal Fluid pH Homeostasis
Acidosis‐Induced Enhanced Activity of the Na‐K Exchange Pump in the In Vivo Choroid Plexus: An Ontogenetic Analysis of Possible Role in Cerebrospinal Fluid pH Homeostasis
复制标题
酸中毒诱导的体内脉络丛 Na-K 交换泵活性增强：脑脊液 pH 稳态中可能作用的个体发生分析
DOI：
10.1111/j.1471-4159.1982.tb08632.x
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发表时间：
1982
影响因子：
4.7
通讯作者：
C. Johanson
中科院分区：
文献类型：
--
作者：
L. Pershing;C. Johanson
摘要：分析了Sprague - Dawley大鼠急性系统性酸中毒后脉络膜上皮细胞[K]和[Na]的变化（反映Na - K泵活性）。代谢性酸中毒1 h后，成年大鼠侧脑室脉络丛（CP）和第4脑室脉络丛（CP）细胞[K]和[Na]分别升高35和15 mm/kg水，表明脑脊液面膜的Na - K交换泵受到明显刺激；相比之下，CP对酸中毒的这种显著反应在未成熟动物（1周龄）中不能引起。由于呼吸性酸中毒对CP细胞[K]和[Na]的影响与代谢性酸中毒相似，血浆pH值（而不是[HCO3]）的降低可能是成人CP中Na和K转换增强的机制。在成熟和未成熟动物急性酸碱扭曲期间，大脑皮层、髓质和脑脊液中Na和K的浓度一般没有改变。受血-脑脊液屏障（CP）和血-脑屏障（BBB）保护的中枢神经系统组织对全身性酸中毒反应的显著差异强调了神经丛的独特作用，可能是体内平衡作用。由于普萘洛尔大大减弱了酸中毒引起的脉络膜细胞[K]和[Na]的变化，因此可能存在β受体对CP中Na，K - atp酶（Na - K泵）的调节。我们假设，在系统性酸中毒中，脑脊液中普遍观察到的增强的正电性至少部分是由CP中Na - K泵的促进引起的，尽管诱导的膜通透性变化也可能是一个因素。
Abstract: Changes in cellular [K] and [Na] in the choroidal epithelium (as a reflection of Na‐K pump activity) were analyzed in Sprague‐Dawley rats subjected to acute systemic acidosis. In the lateral and 4th ventricle choroid plexus (CP) of adult rats in which metabolic acidosis was induced for 1 h, cell [K] and [Na] increased and decreased by 35 and 15 mm/kg water, respectively, indicating marked stimulation of the Na‐K exchange pump in the CSF‐facing membrane; in contrast, this striking response of the CP to acidosis could not be elicited in immature animals (1 week old). Since the effects of respiratory acidosis on CP cell [K] and [Na] were similar to those of metabolic acidosis, the reduction in plasma pH (rather than in [HCO3]) is likely the mechanism underlying the enhanced turnover of Na and K across the CP in adults. The concentration of Na and K in the cerebral cortex, medulla, and CSF was generally not altered during acute acid‐base distortions in both mature and immature animals. The striking difference in the response of CNS tissue protected by the blood‐CSF barrier (i.e., CP) and the blood‐brain barrier (BBB) to systemic acidosis emphasizes a unique role, presumably homeostatic, for the plexus. Since propranolol substantially attenuated the acidosis‐induced changes in choroidal cell [K] and [Na], it is possible that there is β‐receptor modulation of the Na,K‐ATPase (Na‐K pump) in the CP. We postulate that the generally observed enhanced electropositivity in the CSF in systemic acidosis is brought about, at least in part, by facilitation of Na‐K pumping in the CP, although induced changes in membrane permeability may also be a factor.
碳酸酐酶抑制剂和酸中毒对脉络丛上皮细胞钠和钾的影响。
DOI：
--
发表时间：
1980
期刊：
The Journal of pharmacology and experimental therapeutics
影响因子：
--
作者：
Smith,QR;Johanson,CE
通讯作者：
Johanson,CE
[36Cl]-、[22Na]-和[3H]甘露醇摄入体内脉络丛-脑脊液脑系统的动力学分析：血脑和血-CSF屏障的个体发育。
影响因子：
2.9
作者：
Smith,QR;Woodbury,DM;Johanson,CE
通讯作者：
Johanson,CE