Selective Alterations of Extracellular Brain Amino Acids in Relation to Function in Experimental Portal‐Systemic Encephalopathy: Results of an In Vivo Microdialysis Study
Selective Alterations of Extracellular Brain Amino Acids in Relation to Function in Experimental Portal‐Systemic Encephalopathy: Results of an In Vivo Microdialysis Study
复制标题
与实验性门系统性脑病功能相关的细胞外脑氨基酸的选择性改变：体内微透析研究的结果
DOI：
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发表时间：
1995
影响因子：
4.7
通讯作者：
R. Butterworth
中科院分区：
文献类型：
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作者：
V. L. Raghavendra Rao;R. Audet;R. Butterworth
Abstract: Portal‐systemic encephalopathy (PSE) is characterized by neuropsychiatric symptoms progressing through stupor and coma. Previous studies in human autopsy tissue and in experimental animal models of PSE suggest that alterations in levels of brain amino acids may play a role in the pathogenesis of PSE. To assess this possibility, levels of amino acids were measured using in vivo cerebral microdialysis in frontal cortex of portacaval‐shunted rats administered ammonium acetate (3.85 mmol/kg, i.p.) to precipitate severe PSE. Sham‐operated rats served as controls. Portacaval shunting resulted in significant increases of levels of extracellular glutamine (threefold, p < 0.001), alanine (38%, p < 0.01), aspartate (44%, p < 0.05), phenylalanine (170%, p < 0.001), tyrosine (140%, p < 0.001), tryptophan (63%, p < 0.001), leucine (75%, p < 0.001), and serine (60%, p < 0.001). Administration of ammonium acetate to sham‐operated animals led to a significant increase in extracellular glutamine and taurine content, but this response was absent in shunted rats. The lack of taurine release into extracellular fluid following ammonium acetate administration in portacaval‐shunted rats could relate to the phenomenon of brain edema in these animals. Ammonium acetate administration resulted in significant increases in the extracellular concentrations of phenylalanine and tyrosine in both sham‐operated and portacaval‐shunted rats. Severe PSE was not accompanied by significant increases in extracellular fluid concentrations of glutamate, aspartate, GABA, tryptophan, leucine, or serine, suggesting that increased spontaneous release of these amino acids in cerebral cortex is not implicated in the pathogenesis of hepatic coma.
DOI：
10.1007/bf02833600
发表时间：
1987
期刊：
Neurochemical pathology
影响因子：
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作者：
Hawkins,RA;Mans,AM;Biebuyck,JF
通讯作者：
Biebuyck,JF