PubMed Health⌕ Search

Biomedical subjects

B Duperray

Publications and source records attributed to B Duperray.

At least 19 recordsLinked to original sources
PubMed1991

Distribution of tritium labeled 12(S) hydroxy-eicosatetraenoic acid (12-HETE) in the rat.

The in vivo metabolism of 12-(S)-Hydroxy-eicosatetraenoic acid (12-HETE), the end-lipoxygenase product of arachidonic acid in platelets, has been investigated in the rat. Fifty microcuries of 5,6-[3H]-12-HETE (50 Ci/mmol) were injected to anesthetized rats and the radioactivity was followed in plasma. At the end of the experiment, various organs of the animal were removed and the radioactivity attached to them was determined. The label of the plasma plateaued to approximately one third of the initial radioactivity ten minutes after the injection. Among the various organs tested (brain, heart, intestine, kidney, liver, lungs, spleen, testis/uterus) the kidney was far the most active to accumulate 12-HETE and/or its labeled metabolites, and no radioactivity could be detected in urine during the course of the experiment. The analysis of lipid extracts from the various tissues revealed that 12-HETE was not accumulating in its unesterified form but was likely bound to phospholipids. We conclude that, although the label providing from the initial 12-HETE did not completely disappear from plasma, circulating 12-HETE cannot be considered as a circulating marker of cell activation.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1981

Isotope derivative assay of human serum bile acids.

A new method for the selective determination of the main serum bile acids has been developed. Serum samples with added 14C-labeled bile acid were submitted to deproteinization, alkaline hydrolysis, methylation, and were then chromatographed on alumina before acetylation with 2 microliters of [3H]acetic anhydride. Excess reagent was eliminated by evaporation; elimination of residual tritiated contaminants and separation of the doubly labeled bile acid derivatives were obtained by thin-layer chromatography, column chromatography on Lipidex 5000, and crystallization. The sensitivity of the method is about 10 pmol of each bile acid. Analyses of seven sera with normal or elevated concentration of bile acids by the proposed method and gas-liquid chromatography showed a close correlation (r = 0.94; slope = 0.93).

Bile Acids and Salts↗
PubMed1979

Bile acid sulfates in serum bile acids determination.

Some bile acid sulfates were synthesized and characterized. The configuration of sulfate groups at C-3, C-7 and C-12 positions was confirmed by Nuclear Magnetic Resonance analysis. These sulfates were utilized in a study of their chemical behaviour in different analytical procedures currently used for serum bile acids determination. Procedures for bile acids extraction from serum with ethanol or Amberlite XAD-2 result in an important loss of the most polar sulfated bile acids. Complete separation of unsulfated from sulfated bile acids on Sephadex LH-20 is not achieved when deconjugation of the most polar bile acid sulfate is slow but does not produce artifacts. Enzymatic determination of bile acids gives positive response with some bile acid sulfates. The current procedures of serum bile acids determination are discussed in consideration of these results.

Bile Acids and Salts↗
PubMed1979

[The effect of estradiol benzoate on liver function, cholesterol metabolism and bile acids in the quail].

Immature female quails were treated for 6 days with estradiol benzoate at daily 0.01-, 0.02-, 0.01-, and 1-mg dosages. At the end of treatment, bile outflow, biliary cholesterol (CST), and bile acid (BA) secretory rates and liver, bile, and serum CST and BA levels were determined. Some quails were used to measure the ratio (R) of the rates of intravenously injected [2-14C]acetate radioactivity incorporation in cholic (C) and chenodeoxycholic (CDC) acids excreted in bile. The oestrogenic treatments at doses greater than 0.01 mg/day caused a marked disturbance in hepatic function and in CST and BA metabolism: they induced an increase in relative liver weight, liver CST stores, serum CST, C, CDC, and SGOT levels and in choleresis (respectively up to 56, 57, 650, 6000, 700, 42, and 235% increase at the daily 0.1-mg dosage) and they decreased bile total BA and CDC levels, bile and serum CDC to C level ratios, and R ratio (by 71, 82, 69, 84, and 58%, respectively). An increase in the bile salts independent fraction of bile was responsible for hypercholeresis, whether alone at low dosage or in conjunction with other factors at higher dosage. These results are compared with those obtained in mammals, particularly in the rat.

Animals↗
PubMed1978

[Postprandial variations in serum bile acid levels in humans free of hepatic or intestinal diseases (author's transl)].

The levels of unsulfated, free or conjugated cholic, deoxycholic and chenodeoxycholic acids were measured using gas chromatography in 39 humans free of hepatic or intestinal diseases before and 10, 60, 120 and 180 min after ingestion of a standard meal. The probable maximal levels were determined with an error risk lower than 0.05. In fasting subjects, the observed values are comparable with those obtained by other authors working with gas chromatography or radioimmunoassay. Meal ingestion does not influence in the same way the serum levels of the various bile acids: the chemodeoxycholic serum level rose significantly in all cases whereas cholic and deoxycholic serum levels rose only in two-thirds of observed subjects; 60 and 120 min after the meal for chenodeoxycholic acid, and only 60 min after the meal for cholic acid, the mean values are significantly higher than the fasting ones; 120 min after the meal, the chenodeoxycholic and total bile acid probable maximal levels (respectively 7.4 and 10.3 micrometer) are twice the fasting ones. The cholic to chenodeoxycholic serum level ratio is nearly always lower than 1 but may reach 3. On the basis of these results, the validity and efficacy of the exploration tests based on serum bile acid level determinations are discussed.

Adolescent↗