scholarly journals Observations on the phosphate status and intracellular pH of intact cells, protoplasts and chloroplasts from photosynthetic tissue using phosphorus-31 nuclear magnetic resonance

1982 ◽  
Vol 202 (2) ◽  
pp. 429-434 ◽  
Author(s):  
C Foyer ◽  
D Walker ◽  
C Spencer ◽  
B Mann
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Intracellular Ph ◽  
Inorganic Phosphate ◽  
Spinacia Oleracea ◽  
Fundamental Difference ◽  
Asparagus Officinalis ◽  
Intact Cells ◽  
Spinach Chloroplasts ◽  
Nuclear Magnetic

Individual pools of intracellular inorganic phosphate (Pi) can be observed in the dark in intact cells, protoplasts and chloroplasts from photosynthetic tissue by using 31P nuclear magnetic resonance (n.m.r.). Estimates for the pH of vacuolar and extravacuolar compartments are reported although it is shown that intracellular pH is determined by the pH of the suspending medium. Mannose treatment of asparagus (Asparagus officinalis) cells and spinach (Spinacia oleracea) protoplasts results in the inhibition of photosynthesis. The mechanism of mannose phosphate sequestration of free Pi is supported by the 31P n.m.r. spectra of mannose-treated tissue. There is a fundamental difference in 31 P n.m.r. spectra of mannose-treated spinach protoplasts and asparagus cells, reflecting a difference in the availability of vacuolar Pi for cellular metabolism in these species. The 31P n.m.r. spectrum of intact spinach chloroplasts is reported.

In Vivo 31P Nuclear Magnetic Resonance Measurement of Chronic Changes in Cerebral Metabolites Following Neonatal Intraventricular Hemorrhage

PEDIATRICS ◽  
1988 ◽  
Vol 82 (3) ◽  
pp. 331-336
Author(s):  
Donald Younkin ◽  
Barbara Medoff-Cooper ◽  
Ronnie Guillet ◽  
Teresa Sinwell ◽  
Britton Chance ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Intracellular Ph ◽  
Adenosine Triphosphate ◽  
Inorganic Phosphate ◽  
Intraventricular Hemorrhage ◽  
Metabolic Changes ◽  
31P Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

The purpose of this study was to determine whether cerebral metabolic changes occur after intraventricular hemorrhage in the newborn. Five babies with bilateral grade 3 to 4 intraventricular hemorrhage were compared with 15 preterm infants without intraventricular hemorrhage. Cerebral high-energy phosphorus metabolites and intracellular pH were measured with in vivo 31P nuclear magnetic resonance spectroscopy. Spectra were collected initially within the first 2 weeks of life, and then every other week until discharged from the hospital. The phosphocreatine to inorganic phosphate ratio and the phosphocreatine to adenosine triphosphate ratio were significantly lower in the group with intraventricular hemorrhage, but differences in intracellular pH were not significant. Differences between babies with and without intraventricular hemorrhage varied with postconceptional age: in those with intraventricular hemorrhage, the phosphocreatine to adenosine triphosphate ratio was decreased at all postconceptional ages, and the phosphocreatine to inorganic phosphate ratio was lower in babies with intraventricular hemorrhage and younger than 30 weeks. Results of this study confirm the presence of chronic metabolic changes following intraventricular hemorrhage which may exacerbate neurologic damage after intraventricular hemorrhage in the newborn.

scholarly journals A phosphorus-31 nuclear magnetic resonance investigation of intracellular environment in human normal and sickle cell blood

Blood ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 196-209 ◽  
Author(s):  
YF Lam ◽  
AK Lin ◽  
C Ho
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Intracellular Ph ◽  
Sickle Cell ◽  
Resonance Spectroscopy ◽  
Blood Samples ◽  
Intracellular Environment ◽  
Nuclear Magnetic

Abstract Intracellular pH and 2,3-diphosphoglycerate concentration in sickle cell amenia and normal human blood samples were measured by means of phosphorus-31 nuclear magnetic resonance spectroscopy. To monitor the concentrations of various internal phosphorylated metabolites of intact red blood cells, heparinized blood samples were used and were incubated at 37 degrees C with 5.6% C92, 25% O2, and 69.4% N2. The 31P chemical shifts of phosphorylated compounds, such as 2,3-diphosphoglycerate, adenosine 5′-triphosp-ate, and inorganic phosphate, depend on pH, and by using an appropriate calibration curve, the intracellular pH of intact erythrocytes can be obtained. The intracellular pH values in fresh sickl cell blood and normal blood were found to be 7.14 and 7.29, respectively. However, the whole-blood pH, as measured by a standard pH meter, was found to be 7.54 for both types of blood. The initial concentration of 2,3-diphosphoglycerate in sickle cell blood was about 30% higher, but it was depleted much faster during incubation than that in normal blood. The difference in intracellular pH between these two types of blood samples remained constant during incubation, even after depletion of 2,3-diphosphoglycerate. These results suggest that there are differences in intracellular environment between normal and sickle cell blood. Thus, 31P nuclear magnetic resonance spectroscopy provides a fast, direct, continuous, and noninvasive way to monitor the intracellular environment of intact erythrocytes.

31P-nuclear magnetic resonance analysis of perfused single frog skins

1985 ◽  
Vol 248 (1) ◽  
pp. C177-C180 ◽  
Author(s):  
L. E. Lin ◽  
M. Shporer ◽  
M. M. Civan
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Intracellular Ph ◽  
Nmr Spectra ◽  
Nuclear Magnetic Resonance Analysis ◽  
Resonance Analysis ◽  
31P Nuclear Magnetic Resonance ◽  
Nmr Study ◽  
Order Of Magnitude ◽  
Nuclear Magnetic

Perfusion of single frog skins has produced stability of the 31P-nuclear magnetic resonance (NMR) spectra over periods as long as 8 h at room temperature. With this approach, relatively large phosphocreatine (PCr) signals were recorded for each of the 12 frog skins studied. The ratio of the concentration of PCr to ATP was estimated to be 0.76 +/- 0.07, a value an order of magnitude larger than that previously reported. Comparison of the ratio of the intracellular concentrations of inorganic phosphate (Pi) to ATP determined in the present NMR study with that previously estimated by chemical analysis suggests that little intracellular Pi is likely to be immobilized. Inclusion of methylphosphonate in the perfusing solutions permitted simultaneous determination of extracellular and intracellular pH from the NMR spectra alone. The methylphosphonate has been found to be nontoxic. At an extracellular pH of 7.72 +/- 0.04, the intracellular pH was 7.47 +/- 0.06.

31P nuclear magnetic resonance analysis of frog skin

1982 ◽  
Vol 243 (1) ◽  
pp. C74-C80 ◽  
Author(s):  
L. E. Lin ◽  
M. Shporer ◽  
M. M. Civan
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Epithelial Cells ◽  
Inorganic Phosphate ◽  
Frog Skin ◽  
Short Circuit ◽  
Toad Bladder ◽  
Nuclear Magnetic Resonance Analysis ◽  
31P Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

The intracellular phosphate composition of whole and split frog skins has been studied by 31P nuclear magnetic resonance (NMR) analysis. The spectra were similar to those previously recorded from isolated epithelial cells of toad bladder. However, qualitative differences were noted in comparison with spectra from whole toad bladder. The 31P spectra from whole frog skin reflect the intracellular compositions of the epithelial cells, whereas subepithelial elements contribute significantly to the total observed 31P signals from toad bladder. Analyzed at 4 degrees C, the average phosphocreatine (PCr) and ATP concentrations of frog skin are of similar magnitude. The ratio of [PCr] to [ATP + ADP] depends on time, tissue oxygen tension, temperature, and extracellular inorganic phosphate concentration. Both this ratio and the short-circuit current (measured in parallel experiments) fell during the course of aerating frog skins in Ringer solution at room temperature. The intracellular inorganic phosphate (Pi) signal was identified. After reduction of extracellular pH, the signal did not shift immediately but subsequently did undergo an acid shift.

Sign in / Sign up

Export Citation Format

Share Document