Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
HYPERAMMONEMIA-INDUCED DEPLETION OF GLUTAMATE AND BRANCHED-CHAIN AMINO-ACIDS IN MUSCLE AND PLASMA
Autore:
LEWELING H; BREITKREUTZ R; BEHNE F; STAEDT U; STRIEBEL JP; HOLM E;
Indirizzi:
UNIV HEIDELBERG,DEPT PATHOPHYSIOL,MED CLIN 1,THEODOR KUTZER UFER D-68167 MANNHEIM GERMANY UNIV HEIDELBERG,DEPT PATHOPHYSIOL,MED CLIN 1 D-68167 MANNHEIM GERMANY
Titolo Testata:
Journal of hepatology
fascicolo: 5, volume: 25, anno: 1996,
pagine: 756 - 762
SICI:
0168-8278(1996)25:5<756:HDOGAB>2.0.ZU;2-3
Fonte:
ISI
Lingua:
ENG
Soggetto:
SKELETAL-MUSCLE; LIVER-CIRRHOSIS; HEPATIC ENCEPHALOPATHY; METABOLISM; INSULIN; ALANINE; AMMONIA; FAILURE; INSUFFICIENCY; IMBALANCE;
Keywords:
BRANCHED-CHAIN AMINO ACIDS; GLUTAMATE; HYPERAMMONIA; MUSCLE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
44
Recensione:
Indirizzi per estratti:
Citazione:
H. Leweling et al., "HYPERAMMONEMIA-INDUCED DEPLETION OF GLUTAMATE AND BRANCHED-CHAIN AMINO-ACIDS IN MUSCLE AND PLASMA", Journal of hepatology, 25(5), 1996, pp. 756-762

Abstract

Background/Aims: Exogenous hyperammonemia is known to decrease the plasma levels of branched-chain amino acids (BCAA), To investigate whether changes in intracellular amino acid concentrations of muscle are associated with and may, at least in part, mediate this effect, experiments were carried out on a total of 60 male Wistar rats. Methods: Five groups were formed in a randomized manner. Group A: no treatment; groups B1 and B2: 2-hour and 6-hour continuous central-venous infusions, respectively, of sodium salts; groups C1 and C2: 2-hour and 6-hour infusions of ammonium salts. We obtained venous blood samples and muscle biopsies. Plasma ammonia, whole blood glucose, serum insulin, blood pH,and amino acids in plasma as well as in the intracellular water of muscle were measured. Results: As compared with control group A, groups C1 and C2 displayed a 3.3- and a 4-fold increase, respectively, in theplasma ammonium concentration. Regarding insulin, the ammonium-infused rats were similar to group A but not to the sodium-infused B groups,which had significantly lower insulin concentrations. Administering ammonium brought about a decline in BCAA concentrations in plasma after2 hours and in muscle after 6 hours. The ammonium-induced fall in intracellular BCAA values was preceded by an increase of glutamine as well as by a decrease of glutamate and alanine in both plasma and muscle. Conclusions: It is pointed out that the inter-group differences in serum insulin, although possibly accounting for some of the findings, can by no means explain the entire pattern of amino acid concentrations seen after the ammonium infusions. Instead, our results agree-with thehypothesis that hyperammonemia indirectly lowers the plasma levels ofBCAA by stimulating glutamine synthesis, thus reducing the intracellular glutamate pool, which is likely to be restored, at least in part, by an intensified BCAA transamination. Clarification is needed as to whether carbon skeletons derived from valine and isoleucine additionally contribute to replenishing the glutamate pool.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 24/09/20 alle ore 04:48:37