+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Complexity of glutamine metabolism in kidney tubules from fed and fasted rats

, : Complexity of glutamine metabolism in kidney tubules from fed and fasted rats. Biochemical Journal 378(Pt 2): 485-495

Glutamine is an important renal glucose precursor and energy provider. In order to advance our understanding of the underlying metabolic processes, we studied the metabolism of variously labelled [13C]glutamine and [14C]glutamine molecules and the effects of fasting in isolated rat renal proximal tubules. Absolute fluxes through the enzymes involved, including enzymes of four different cycles operating concomitantly, were assessed by combining mainly the 13C NMR data with an appropriate model of glutamine metabolism. In both nutritional states, unidirectional glutamine removal by glutaminase was partially masked by the concomitant operation of glutamine synthetase; fasting accelerated glutamine removal by increasing flux solely through glutaminase, without changing that through glutamine synthetase. Fasting stimulated net glutamate degradation only by decreasing flux through glutamate dehydrogenase in the reductive amination direction, but surprisingly did not significantly alter complete oxidation of the glutamine carbon skeleton. Finally, gluconeogenesis from glutamine involved not only substantial recycling through the tricarboxylic acid cycle, but also an important anaplerotic flux through pyruvate carboxylase that was accelerated dramatically by fasting. Thus renal glutamine metabolism follows an unexpectedly complex route that is precisely regulated during fasting.


PMID: 14616091

DOI: 10.1042/BJ20031088

Other references

Takahashi H.; Wakasa H., 1982: Angio immuno blastic lymph adenopathy light microscopic and electron microscopic studies. The significance of clinical and histologic features in 16 [human] cases of angioimmunoblastic lymphadenopathy (AIL) were evaluated. The disease observed in the elderly is characterized by an acute onset of constitutional symptoms, generalized lym...

Chand, P.K.; Anand, S.; Murthy, P., 2005: Monosymptomatic hypochondriacal psychosis: atypical presentation and response to olanzapine. Journal of Clinical Psychiatry 66(6): 800-801

Fogel M.A.; Seliem M.; Lieb D.R., 1991: Do electrocardiographic criteria for left ventricular hypertrophy in children with pressure or volume loaded ventricles really work. Pediatric Research 29(4 PART 2): 18A

Nugent, M.E., 2011: Budget planning under payment reform. Healthcare reform makes budgeting topline reimbursement, volume, payer mix, and collections more difficult than in the past. Finance should take the lead at educating physicians and operators on what reform will mean to unit reimbursement, collect...

Kummer, H.; Bucher, U., 1965: Experiences with a new cytostatic of the methylhydrazine series (Natulan). With special reference to hematological side-effects. Schweizerische Medizinische Wochenschrift 95(37): 1233-1240

Han S.U.; Choi S.K., 1985: Estimates of heritability and genetic gain for height growth of open pollinated plus trees of korean pine pinus koraiensis. Open-pollinated progeny tests with 19 plus trees of Pinus koraiensis were established in 3 different locations. Tenth year heights were heights were highly variable among locations from 103.1 cm to 194.9 cm. Estimates of individual tree heritabili...

Cortés Hernández, F.; Falcó Ferrer, V.; Martínez Orfila, J.A.; Sainz, B.; Royo Lázaro, J.; Armengol Carrasco, M.; Fernández de Sevilla Ribosa, T., 1996: Progressive abdominal distension in a 57-year-old male. Revista Clinica Espanola 196(12): 859-860

Mini, C.; Vahab, M.A., 2000: Evaluation of capsicum genotypes for oleoresin recovery with respect to season and harvest maturity. Influence of three stages of harvest maturity in three seasons on the fruit and oleoresin yield was studied in nine different chilli (Capsicum frutescens) genotypes. Pooled analysis showed significant differences among genotypes for all the charac...

Bowles, D.K.; Ganjam, V.; Rubin, L.J.; Maddali, K.K.; Tharp, D.L.; Mester, R.A.; Heaps, C.L., 2004: Endogenous testosterone increases expression and activity of L-type Ca2+ channels in coronary smooth muscle. Evidence indicates that gender and sex hormonal status influence cardiovascular physiology and pathophysiology. We recently demonstrated increased L-type voltage-gated Ca2+ current (ICa) in coronary smooth muscle (CSM) of male swine compared to fe...

Ma, J.; Li, S.; Reed, K.; Guo, P.; Gallo, J.M., 2003: Pharmacodynamic-mediated effects of the angiogenesis inhibitor SU5416 on the tumor disposition of temozolomide in subcutaneous and intracerebral glioma xenograft models. The objective of this study was to determine the tumor distribution of temozolomide, an alkylating agent, in the absence and presence of the angiogenesis inhibitor 3-[(2,4-dimethylpyrrol-5-yl)methylidenyl]indolin-2-one (SU5416), a specific vascula...