Abstract
The cerebral metabolism of amino acids (AA) and ammonia in the postabsorptive state was evaluated in 8 subjects with normal renal function and in 6 patients with chronic renal insufficiency (CRI) by measuring the differences between the arterial and the internal jugular venous concentrations of free AA and ammonia. In normal conditions, the brain extracts serine, glutamine, proline, glycine, valine, 1/2 cystine, isoleucine, leucine, and lysine. In CRI, cerebral glycine and 1/2 cystine uptake increases, valine and isoleucine extraction decreases, glutamine uptake disappears, and ammonia extraction becomes evident. The cerebral extraction of glycine is correlated with the arterial concentration of glycine, serine, and branched-chain AA. The extraction of 1/2 cystine is correlated with the arterial concentration of 1/2 cystine and tyrosine. Finally, the extractions of valine and ammonia are correlated with the arterial concentration of valine and ammonia, respectively. It follows that alterations of blood AA and ammonia concentrations observed in CRI markedly affect the cerebral uptake of some AA and ammonia. The lack of cerebral glutamine extraction might be due to an enhanced production and/or, more likely, to an impaired utilization of this AA by the brain. Data reported here suggest that in CRI cerebral nitrogen metabolism is altered; such alterations may play a pathogenic role in uremic encephalopathy.
| Original language | English |
|---|---|
| Pages (from-to) | 505-510 |
| Number of pages | 6 |
| Journal | Kidney International |
| Volume | 20 |
| Issue number | 4 |
| Publication status | Published - 1981 |
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ASJC Scopus subject areas
- Nephrology
Cite this
Brain metabolism of amino acids and ammonia in patients with chronic renal insufficiency. / Deferrari, G.; Garibotto, G.; Robaudo, C.; Ghiggeri, G. M.; Tizianello, A.
In: Kidney International, Vol. 20, No. 4, 1981, p. 505-510.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Brain metabolism of amino acids and ammonia in patients with chronic renal insufficiency
AU - Deferrari, G.
AU - Garibotto, G.
AU - Robaudo, C.
AU - Ghiggeri, G. M.
AU - Tizianello, A.
PY - 1981
Y1 - 1981
N2 - The cerebral metabolism of amino acids (AA) and ammonia in the postabsorptive state was evaluated in 8 subjects with normal renal function and in 6 patients with chronic renal insufficiency (CRI) by measuring the differences between the arterial and the internal jugular venous concentrations of free AA and ammonia. In normal conditions, the brain extracts serine, glutamine, proline, glycine, valine, 1/2 cystine, isoleucine, leucine, and lysine. In CRI, cerebral glycine and 1/2 cystine uptake increases, valine and isoleucine extraction decreases, glutamine uptake disappears, and ammonia extraction becomes evident. The cerebral extraction of glycine is correlated with the arterial concentration of glycine, serine, and branched-chain AA. The extraction of 1/2 cystine is correlated with the arterial concentration of 1/2 cystine and tyrosine. Finally, the extractions of valine and ammonia are correlated with the arterial concentration of valine and ammonia, respectively. It follows that alterations of blood AA and ammonia concentrations observed in CRI markedly affect the cerebral uptake of some AA and ammonia. The lack of cerebral glutamine extraction might be due to an enhanced production and/or, more likely, to an impaired utilization of this AA by the brain. Data reported here suggest that in CRI cerebral nitrogen metabolism is altered; such alterations may play a pathogenic role in uremic encephalopathy.
AB - The cerebral metabolism of amino acids (AA) and ammonia in the postabsorptive state was evaluated in 8 subjects with normal renal function and in 6 patients with chronic renal insufficiency (CRI) by measuring the differences between the arterial and the internal jugular venous concentrations of free AA and ammonia. In normal conditions, the brain extracts serine, glutamine, proline, glycine, valine, 1/2 cystine, isoleucine, leucine, and lysine. In CRI, cerebral glycine and 1/2 cystine uptake increases, valine and isoleucine extraction decreases, glutamine uptake disappears, and ammonia extraction becomes evident. The cerebral extraction of glycine is correlated with the arterial concentration of glycine, serine, and branched-chain AA. The extraction of 1/2 cystine is correlated with the arterial concentration of 1/2 cystine and tyrosine. Finally, the extractions of valine and ammonia are correlated with the arterial concentration of valine and ammonia, respectively. It follows that alterations of blood AA and ammonia concentrations observed in CRI markedly affect the cerebral uptake of some AA and ammonia. The lack of cerebral glutamine extraction might be due to an enhanced production and/or, more likely, to an impaired utilization of this AA by the brain. Data reported here suggest that in CRI cerebral nitrogen metabolism is altered; such alterations may play a pathogenic role in uremic encephalopathy.
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UR - http://www.scopus.com/inward/citedby.url?scp=0019446189&partnerID=8YFLogxK
M3 - Article
C2 - 7311310
AN - SCOPUS:0019446189
VL - 20
SP - 505
EP - 510
JO - Kidney International
JF - Kidney International
SN - 0085-2538
IS - 4
ER -