scholarly journals Crenarchaea and phytoplankton coupling in sedimentary archives: Common trigger or metabolic dependence?

2011 ◽  
Vol 56 (5) ◽  
pp. 1907-1916 ◽  
Author(s):  
Susanne Fietz ◽  
Alfredo Martínez-Garcia ◽  
Gemma Rueda ◽  
Vicky L. Peck ◽  
Carme Huguet ◽  
...  
Keyword(s):  
Metabolic Dependence

Metabolic dependence of the electromyogram of the cat colon

1980 ◽  
Vol 239 (3) ◽  
pp. G173-G176 ◽  
Author(s):  
S. Anuras ◽  
S. M. Chien ◽  
J. Christensen
Keyword(s):  
Slow Wave ◽  
Distal Colon ◽  
Proximal Colon ◽  
Wave Frequency ◽  
Reduced Frequency ◽  
Metabolic Dependence ◽  
Spike Bursts

Strips of colon muscle (1 x 10 cm) were exposed to alterations of temperature, to 2,4-dinitrophenol, and were deprived of O2. Cooling reduced slow-wave frequency in proximal colon from 5.2 at 37 degrees C to 3.9, 2.7, 1.2 and 0.5 cycle/min at 34, 30, 25, and 20 degrees C, respectively; all changes were significant (P < 0.05). Heating also reduced slow-wave frequency in proximal colon from 5.2 at 37 degrees C to 5.1, 4.8 (P < 0.05), and 3.3 (P < 0.05) cycle/min at 39, 41, and 43 degrees C, respectively. Hypoxia reduced slow-wave frequency from 4.6 at 95% O2 to 2.8 cycle/min at 0% O2 (P < 0.05). 2,4-Dinitrophenol (10(-4) M) reduced frequency from 5.3 to 2.7 cycle/min (P < 0.05). The results of studies of distal colon were similar. In distal colon cooling reduced the time occupied by migrating spike bursts from 20.7% at 37 degrees C to 11.1% at 25 degrees C, and 7.9% at 20 degrees C (P < 0.05). Hypoxia also reduced the time occupied by migrating spike bursts from 16.7% at 95% O2 to 5.9% at 0% O2 (P < 0.05).

Cell volume and metabolic dependence of NEM-activated K+-Cl- flux in human red blood cells

1985 ◽  
Vol 249 (1) ◽  
pp. C124-C128 ◽  
Author(s):  
P. K. Lauf ◽  
C. M. Perkins ◽  
N. C. Adragna
Keyword(s):  
Red Blood Cells ◽  
Cell Volume ◽  
Blood Cells ◽  
Time Course ◽  
Transport Activity ◽  
Human Red Blood Cells ◽  
Atp Breakdown ◽  
The Difference ◽  
Metabolic Dependence ◽  
K Transport

The effects of incubation in anisosmotic media and of metabolic depletion on ouabain-resistant (OR) Cl--dependent K+ influxes stimulated by N-ethylmaleimide (NEM) were studied in human red blood cells using Rb+ as K+ analogue. The NEM-stimulated but not the basal Rb+-Cl- influx measured in phosphate-buffered anisosmotic media was found to be cell volume dependent. When cellular ATP, [ATP]c, was lowered to less than 0.10 of its initial level by exposure to nonmetabolizable 2-deoxy-D-glucose, the NEM-stimulated but not the basal Cl--dependent Rb+ influxes were abolished. Metabolically depleted red blood cells subsequently repleted by incubation in glucose plus inosine regained the NEM-inducible Rb+ (K+) transport activity. The difference in the time course of ATP breakdown and Rb+ influx inhibition suggests that energization of the NEM-stimulated Rb+ flux by metabolism may involve factors additional to ATP.

scholarly journals Membrane potentials and resistances of giant mitochondria. Metabolic dependence and the effects of valinomycin.

1978 ◽  
Vol 78 (1) ◽  
pp. 199-213 ◽  
Author(s):  
B L Maloff ◽  
S P Scordilis ◽  
C Reynolds ◽  
H Tedeschi
Keyword(s):  
Membrane Potential ◽  
Membrane Potentials ◽  
The Other ◽  
Metabolic State ◽  
Giant Mitochondria ◽  
Internal Concentration ◽  
Diffusion Potentials ◽  
K Concentration ◽  
Metabolic Dependence

The membrane potentials and resistances of giant mitochondria from mice fed cuprizone have been studied. They were found to correspond approx. 10-20 mV, positive inside, and 2 M omega, respectively. These properties were found to be independent of the metabolic state. The microelectrodes were in the inner mitochondrial space since (a) the potentials in the presence of valinomycin depended on the K+ concentration of the medium and magnitude of the K+ diffusion potentials was consistent with the presence of a high internal concentration of K+, (b) almost identical results were obtained with mitochondria from which the external membrane had been removed and the cristae were evaginated, and (c) punch-through experiments, in which the microelectrodes were advanced until they emerged through the other side of the mitochondria, showed an identical membrane potential both in the presence and in the absence of valinomycin. The potentials were stable under a variety of conditions and showed no sign of decay of membrane leakiness. Detailed evidence that the impaled mitochondria are metabolically viable will be presented in a separate publication.

Metabolic Dependence of Green Tea on Plucking Positions Revisited: A Metabolomic Study

2011 ◽  
Vol 59 (19) ◽  
pp. 10579-10585 ◽  
Author(s):  
Jang-Eun Lee ◽  
Bum-Jin Lee ◽  
Jeong-ah Hwang ◽  
Kwang-Sup Ko ◽  
Jin-Oh Chung ◽  
...  
Keyword(s):  
Green Tea ◽  
Metabolic Dependence ◽  
Metabolomic Study

scholarly journals In Vivo Metabolism of [1,6-13C2]Glucose Reveals Distinct Neuroenergetic Functionality between Mouse Hippocampus and Hypothalamus

Metabolites ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 50
Author(s):  
Antoine Cherix ◽  
Rajesh Sonti ◽  
Bernard Lanz ◽  
Hongxia Lei
Keyword(s):  
Metabolic Flux ◽  
Aerobic Glycolysis ◽  
Resonance Spectroscopy ◽  
Flux Analysis ◽  
Gamma Aminobutyric Acid ◽  
Atp Production ◽  
Functional Features ◽  
Metabolic Dependence ◽  
The Brain

Glucose is a major energy fuel for the brain, however, less is known about specificities of its metabolism in distinct cerebral areas. Here we examined the regional differences in glucose utilization between the hypothalamus and hippocampus using in vivo indirect 13C magnetic resonance spectroscopy (1H-[13C]-MRS) upon infusion of [1,6-13C2]glucose. Using a metabolic flux analysis with a 1-compartment mathematical model of brain metabolism, we report that compared to hippocampus, hypothalamus shows higher levels of aerobic glycolysis associated with a marked gamma-aminobutyric acid-ergic (GABAergic) and astrocytic metabolic dependence. In addition, our analysis suggests a higher rate of ATP production in hypothalamus that is accompanied by an excess of cytosolic nicotinamide adenine dinucleotide (NADH) production that does not fuel mitochondria via the malate-aspartate shuttle (MAS). In conclusion, our results reveal significant metabolic differences, which might be attributable to respective cell populations or functional features of both structures.

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