Quantitative analysis of unlabelled and polydeuterated compounds by gas chromatography-mass spectrometry

Axelson, Magnus; Cronholm, Tomas; Curstedt, Tore; Reimendal, Robert.; Sjövall, Jan

doi:10.1007/bf02268331

Cited by 63 publications

(18 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Repetitive magnetic scanning (ten scans/min) over the range of mass : charge ratios (m/z) 1-800 daltons per unit electronic charge was initiated after a suitable delay from the time of sample injection. Methods for the computerized evaluation of the mass spectral data have been described (Axelson, Cronholm, Curstedt et al 1974;Alexson & Sjövall, 1977). Higher sensitivity of the GC-MS analyses was obtained by using a single ion monitoring procedure (Axelson et al 1981).…”

Section: Neutral Compounds (Including 3-oxosteroids)mentioning

confidence: 99%

Identification of the major steroids in ovarian and adrenal venous plasma of the brush-tail possum (Trichosurus vulpecula) and changes in the peripheral plasma levels of oestradiol and progesterone during the reproductive cycle

Curlewis¹,

Axelson²,

Stone³

1985

Journal of Endocrinology

Self Cite

View full text Add to dashboard Cite

The quantitatively major steroid hormones in ovarian and adrenal venous plasma of the female brush-tail possum were identified by gas chromatography-mass spectrometry. The ovarian vein plasma samples all contained oestradiol and its concentration was highest during the pro-oestrous phase of the reproductive cycle. During this phase the concentration of progesterone was below the limit of detection but at day 13 of the oestrous cycle and pregnancy, the concentration of progesterone exceeded that of oestradiol. Cortisol and corticosterone were the major steroid hormones found in all adrenal vein samples with cortisol predominant. Androgens with a 3-oxo structure, if present, were below the limits of detection in all plasma samples. Radioimmunoassays for the measurement of progesterone and oestradiol in peripheral plasma were used to follow changes in the concentrations of these steroids during the reproductive cycle. Progesterone in serial blood samples was low at oestrus, rose gradually until day 7 and then increased more rapidly to reach a peak level of 21-29 nmol/l at around day 13. Any differences between the pregnant and non-pregnant cycles were minor. Oestradiol was only detected around oestrus when levels were variable (53.3 +/- 20.92 (S.E.M.) pmol/l; n = 4). The results indicate that the reproductive cycle of the brush-tail possum is characterized by a single peak of oestradiol at around pro-oestrus followed by gradually increasing levels of progesterone. Pregnancy appears to have no influence on the circulating concentrations of oestradiol or progesterone.

show abstract

Section: Neutral Compounds (Including 3-oxosteroids)mentioning

confidence: 99%

Identification of the major steroids in ovarian and adrenal venous plasma of the brush-tail possum (Trichosurus vulpecula) and changes in the peripheral plasma levels of oestradiol and progesterone during the reproductive cycle

Curlewis¹,

Axelson²,

Stone³

1985

Journal of Endocrinology

Self Cite

View full text Add to dashboard Cite

show abstract

“…G.l.c./mass spectrometry was carried out with an LKB 9000 instrument by repetitive accelerating-voltage scanning and magnetic-tape recording as previously described (Axelson et al, 1974). The abundances of molecules having different numbers of deuterium atoms were determined as previously described (Curstedt & Sj6vall, 1974;Curstedt, 1974b;Blomberg & Cronholm, 1979).…”

Section: Isolation and Analysis Of Metabolitesmentioning

confidence: 99%

Heterogeneity of the sn-glycerol 3-phosphate pool in isolated hepatocytes, demonstrated by the use of deuterated glycerols and ethanol

Cronholm¹,

Curstedt²

1984

Biochemical Journal

View full text Add to dashboard Cite

Hepatocytes were isolated from female rats and incubated with [1,1,3, or [2-2H]glycerol. The deuterium excess in phosphatidylcholines, sn-glycerol 3-phosphate and other organic acids was determined by g.l.c./mass spectrometry. The unlabelled fraction of the major phosphatidylcholines decreased exponentially, and the turnover was not changed by the presence of ethanol. The relative contribution of the two deuterated glycerols was about the same in the major phosphatidylcholine as in sn-glycerol 3-phosphate, indicating that formation by acylation ofdihydroxyacetone phosphate is insignificant. [1,1,3,3-2H4]Glycerol had lost deuterium to a larger extent when it was incorporated in the phosphatidylcholine than when it was incorporated in sn-glycerol 3-phosphate, indicating that the phosphatidylcholines are formed from a separate pool ofsn-glycerol 3-phosphate. Deuterium at C-2 was transferred between sn-glycerol 3-phosphate molecules to about 25%. Ethanol decreased the extent of deuterium transfer, the extent of glycerol uptake and the loss of deuterium at C-I and C-3 in sn-glycerol 3-phosphate. The results indicate that the oxidation to dihydroxyacetone phosphate was inhibited by the NADH formed during ethanol oxidation.[2-2H]Glycerol also labelled an alcohol dehydrogenase substrate, malate and lactate, indicating oxidation ofsn-glycerol 3-phosphate in the cytosol. The two acids appeared to be formed in reductions with different pools of NADH.

show abstract

“…with an LKB 9000 instrument, using repetitive accelerating voltage scanning as previously described (Axelson et al, 1974;Blomberg & Cronholm, 1979 . The mass spectrum showed that the ion at m/z 1 5 contained all four, and that at m/z 114 only three, of the methylene hydrogen atoms in succinate.…”

Section: Analytical Proceduresmentioning

confidence: 99%

Incorporation of the 1-pro-R and 1-pro-S hydrogen atoms of ethanol in the reduction of acids in the liver of intact rats and in isolated hepatocytes

Cronholm¹

1985

Biochemical Journal

View full text Add to dashboard Cite

Ethanol oxidation causes redox effects. The coupling of this oxidation via NADH to intermediary metabolism was studied in order to reveal the underlying mechanisms.Isolated rat hepatocytes were incubated with [1,1-2H2j-, (lR The interference of ethanol with the metabolism in liver is to a large extent due to the NADH produced in the oxidations catalysed by alcohol dehydrogenase and aldehyde dehydrogenase (Reitz, 1979). The utilization of this NADH in reductions of tricarboxylic-acid-cycle and related acids has been studied in intact rats with ethanol species having 2H at C-1 Blomberg & Cronholm, 1979). The relative utilization of the l-pro-R and 1 -pro-S hydrogen atoms was different in the reductive formation of lactate, /3-hydroxybutyrate and malate, indicating heterogeneity of the cytosolic and mitochondrial NADH pools. It was considered that similar experiments should be carried out with isolated hepatocytes, since this would eliminate heterogeneity due to differences in oxygenation in different parts of the liver lobuli, and since incubations permit addition of substrates and drugs.Acetaldehyde is generally considered to be oxidized mainly in the mitochondria, but it is not known to what extent extramitochondrial aldehyde dehydrogenases might contribute (Weiner, 1979). Therefore inhibitors for the mitochondrial enzyme were used in experiments on intact rats and in incubations of hepatocytes in order to study if the 1-pro-S hydrogen atom would appear to a larger extent in products formed in cytosolic reductions, as would be the case if acetaldehyde were oxidized in the cytosol.

show abstract

Quantitative analysis of unlabelled and polydeuterated compounds by gas chromatography-mass spectrometry

Cited by 63 publications

References 11 publications

Identification of the major steroids in ovarian and adrenal venous plasma of the brush-tail possum (Trichosurus vulpecula) and changes in the peripheral plasma levels of oestradiol and progesterone during the reproductive cycle

Identification of the major steroids in ovarian and adrenal venous plasma of the brush-tail possum (Trichosurus vulpecula) and changes in the peripheral plasma levels of oestradiol and progesterone during the reproductive cycle

Heterogeneity of the sn-glycerol 3-phosphate pool in isolated hepatocytes, demonstrated by the use of deuterated glycerols and ethanol

Incorporation of the 1-pro-R and 1-pro-S hydrogen atoms of ethanol in the reduction of acids in the liver of intact rats and in isolated hepatocytes

Contact Info

Product

Resources

About