Sensitive high-performance liquid chromatographic assay for the determination of eugenol in body fluids

The high-performance liquid chromatographic assay described permitted a simple, rapid, sensitive, selective and precise quantitative determination of eugenol in body fluids (serum, urine and bile) without derivatization. Amounts in the range 0.02-100 micrograms of eugenol per millilitre of body fluid were determined with intra-assay coefficients of variation below 4% (3.72-1.13%). The short analysis time for each sample and the selectivity even at low concentrations made this assay suitable for pharmacokinetic studies. Eugenol undergoes a pronounced first-pass effect; in serum, unconjugated eugenol was not detected after an oral dose of 150 mg. The kinetics of eugenol conjugates were measured. More than 80% of the dose was excreted within 6 h after oral administration.

High-performance liquid chromatographic analysis of doxacurium, a new long-acting neuromuscular blocker

A rapid and sensitive high-performance liquid chromatographic procedure was developed for the analysis of the new, long-acting neuromuscular blocker doxacurium in the plasma and urine of dog and man and in the bile of dog. Samples were prepared on solid-phase extraction cartridges containing a methyl (C1) bonded phase and were chromatographed on a 15 cm reversed-phase column (C1) using a mobile phase of 0.05 M monobasic potassium phosphate-acetonitrile (30:70, v/v). The compound was detected at 210 nm with a lower limit of quantitation of 10 ng/ml. An inter-assay accuracy of 90-92% was obtained for the analysis of the drug from biological fluids. The method was applied to studies of doxacurium after intravenous administration to dog and man.

Effects of a concanavalin A-binding biliary glycoprotein on nucleation time of gallbladder bile

A study was performed to determine quantitative differences in the total protein concentration of gallbladder bile from gallstone patients and to isolate nucleation-promoting factors from the bile. Total protein concentrations in cholesterol gallstone bile (3.6 +/- 0.6 mg/ml, mean +/- SD, n = 10), calcium bilirubinate gallstone bile (4.2 +/- 1.1 mg/ml, n = 10), black pigment gallstone bile (1.9 +/- 0.6 mg/ml, n = 4) and control gallbladder bile (2.3 +/- 0.5 mg/ml, n = 9) were not significantly different. Also no statistically significant differences in cholesterol saturation index were found among these groups. Gallbladder bile from cholesterol gallstone patients showed significantly faster nucleation than that of controls, calcium bilirubinate gallstone, or black pigment gallstone patients. We partially purified biliary glycoproteins proteins from cholesterol gallstone bile or calcium bilirubinate gallstone bile by chromatography on concanavalin A Sepharose. Nucleation time was measured following the addition of these proteins to control bile in vitro. The glycoproteins obtained from cholesterol gallstone bile had significant nucleation-promoting activity, but nucleation time was not changed following the addition of biliary glycoproteins from calcium bilirubinate gallstone patients. These results suggest that qualitative differences in individual proteins of gallbladder bile are responsible for nucleation-promoting activity in vitro.

Simple enzymatic assay for determining cholesterol concentrations in bile

We use bilirubin oxidase (EC 1.3.3.5) to remove interference by bilirubin in the assay of cholesterol concentration in bile by standard enzymatic methods. Samples are treated for 10 min with nonlimiting amounts of bilirubin oxidase to form biliverdin from bilirubin before the reagent for cholesterol is added. The relatively small interference by biliverdin is easily eliminated by use of sample blanks. The method is simple, convenient, and not hampered by the "chromogen oxidase" activity (the inherent ability of bilirubin oxidase to oxidize some chromogens) that plagues other assays of this type. Using this assay, we have accurately and precisely determined the concentration of cholesterol in bile. Such elimination of bilirubin will also be useful in assays of other biliary constituents or constituents of urine or icteric plasma.

Comparative sequential changes in serum and biliary levels of bile acid components after a single dose of D-galactosamine or partial hepatectomy in the rat

In order to characterize changes in bile acid profile during liver cell damage and regeneration, levels of bile acids in serum and bile were determined by high performance liquid chromatography (HPLC) in F344 rats treated with a single dose of D-galactosamine (galactosamine, 300 mg/kg, i.p.) or subjected to two-thirds partial hepatectomy (PH). In the serum, galactosamine caused elevation of conjugated bile acids such as taurocholic acid (TCA) and tauro-beta-muricholic acid (T beta MCA) at the 24 and 48-h time points, whereas unconjugated bile acids including cholic acid (CA) at 24 h and hyodeoxycholic acid (HDCA) at 48 h were increased after PH. In the bile, elevation of TCA showed most remarkable elevation at the 24-h time point in the galactosamine-treated group. All components of biliary bile acids showed rapid decreases from 24 to 48 h. The results demonstrated that while liver tissue damaged by galactosamine is able to conjugate bile acids it allows leakage into the blood stream. In contrast, the results for rats subjected to PH indicated that liver cells during DNA synthesis are not capable of conjugating all free bile acids with taurine although a similar leakage occurs. It is concluded that obvious elevation of serum TCA or CA and biliary T beta MCA could be a useful indicator of hepatocellular proliferation.

Fetal intestinal obstruction: necessity for percutaneous umbilical blood sampling to assess the severity of Rh sensitization

Investigation into the severity of hemolytic disease due to Rh isoimmunization may be complicated by concurrent amniotic fluid contamination with bile. We have presented a case in which a prenatal sonogram showed evidence of fetal intestinal obstruction, which was subsequently confirmed postpartum by exploratory laparotomy. Since intrauterine regurgitation of bile occurs with intestinal obstruction distal to the papilla of Vater, percutaneous umbilical blood sampling is necessary to discern the presence and severity of hemolytic disease as indicated by an abnormal spectrophotometric absorption pattern.

Rapid isolation of vesicular and micellar carriers of biliary lipids by ultracentrifugation

A simple, rapid, and new method has been developed to isolate and to quantitate the vesicular carrier of biliary lipids by isopycnic ultracentrifugation. The method combines the use of Metrizamide, as an inert centrifugation media to change the density of bile for isopycnic separation of vesicles, and a vertical rotor, to decrease both the time of centrifugation and the pressure of the hydrostatic column in the ultracentrifuge tube. Vesicles harvested from bile-Metrizamide density gradients were identified by negative staining electron microscopy. The buoyant densitites of biliary vesicles varied between 1.010 and 1.030 g/ml. The diameter of vesicles in fractions with d less than 1.020 g/ml was 82 +/- 10 nm and in fraction with d approximately 1.030 g/ml was 57 +/- 8 nm. Gel filtration chromatography with Ultrogel AcA 34 was used to validate the quantitive isolation of vesicles by the ultracentrifugal method. In experiments with bile-Metrizamide continuous preformed density gradients, greater than 93% of vesicular cholesterol was found in fractions with d less than 1.030 g/ml after 285 min of centrifugation at 50,000 rpm in a VTi vertical rotor (Beckman Instruments, Inc.). When 16% Metrizamide was dissolved in bile and centrifuged for 120 min, greater than 96% of total vesicular cholesterol was found in the top 0.4 ml of the 5-ml centrifuge tube, as assessed by gel filtration chromatography. This fraction contained less than 8% of cholesterol carried in micelles, as assessed by gel filtration chromatography. The variation coefficient of this short ultracentrifugal method to isolate biliary vesicles was 4.6%.(ABSTRACT TRUNCATED AT 250 WORDS)

Simultaneous determination of conjugated bile acids in human bile

We describe an optimized liquid chromatographic method for simultaneous analysis of 10 conjugated bile acids in gall bladder and ductal bile. A quick and effective one-step purification with Sep-pak C-18 was adopted. We used a reverse phase C18 stainless steel column and an isocratic mobile phase in a flow programme and monitored the column effluent at 205 nm. The within-day CV ranged from 0.3 to 1.8%, and the between-day CV from 1.2 to 7.2%. Absolute analytical recovery ranged from 89 to 107%. Linearity ranged from 0.3 to 3 mg/mL for most bile acids. The chromatographic analysis was completed in 18 min.

[Analysis of bile and gallstones in 116 patients with symptomatic cholelithiasis]

Gallbladder bile and stones were obtained at 116 cholecystectomies for symptomatic gallstone disease. All 33 patients younger than 50 years had cholesterol stones, whereas 40% of the older patients had pigment stones. We compared the reliability for the differentiation between these two stone types of three different bile tests: cholesterol saturation index, examination of fresh gallbladder bile for presence of cholesterol monohydrate crystals, and nucleation time of ultrafiltered gallbladder bile. Only examination of fresh gall bladder bile for presence of cholesterol crystals was specific and reasonably sensitive for cholesterol gallstone disease regardless of bile concentration. Duodenal bile obtained from 16 patients (10 cholesterol, 6 pigment) before cholecystectomy showed cholesterol crystals in 7 of the cholesterol but in none of the pigment stone patients. This examination may be useful for patient selection for non-operative therapy in gallstone disease, which can only be considered in case of cholesterol gallstones.

The role of glutathione S-transferases in the hepatic metabolism of benzo[a]pyrene in white suckers (Catostomus commersoni) from polluted and reference sites in the Great Lakes

1. Orally administered 3H-benzo[a]pyrene (3H-BaP) was excreted in the bile of White Suckers predominantly as water soluble metabolites some of which were hydrolyzed by arylsulfatase or beta-glucuronidase. 2. Non-hydrolysible polar metabolites comprised a substantial proportion of biliary metabolites. 3. HPLC analysis revealed fluorescent and 3H-labelled peaks which co-eluted with standards of the glucuronide and sulfate conjugates of BaP. 4. The most polar peak co-chromatographed with a double-radiolabelled metabolite produced in vitro with 3H-BaP and 35S-glutathione. 5. Inhibition of epoxide hydrolase in vitro reduced all water soluble metabolites except the glutathione conjugate of BaP. 6. Glutathione conjugation represents a major hepatic detoxication pathway of BaP in White Suckers.

A surgical technique for the long term collection of bile in the pig and measurement of the biliary excretion of copper and zinc

A method is described for surgically modifying the gastrointestinal tract of the pig which enables the long term collection of bile and measurement of bile flow and allows the pig to be kept unrestrained in a large pen. Three surgically prepared gilts grew at an average of 0.79 kg d-1. Bile flow increased with bodyweight from 1.6 ml min-1 at 45 to 50 kg to 3.5 ml min-1 at 124.5 kg bodyweight. Mean output in bile of copper and zinc by the three gilts during the period 08.00 to 12.30 was 161.0 +/- 11.1 and 3.94 +/- 0.41 nmol min-1, respectively. The calculated output during 24 hours represented approximately 5.8 and 0.13 per cent of the daily intake of copper and zinc, respectively.

Qualitative and quantitative comparison of gallbladder proteins from patients with and without cholesterol gallstones

Amino acid analysis and protein electrophoretic techniques were used to determine whether qualitative and quantitative gallbladder protein abnormalities exist in patients with cholesterol gallstones in Inner Mongolia. Gallbladder bile osmotic pressure measurement was determined and correlations were sought between the protein concentration and osmotic pressure of gallbladder bile. Protein concentrations and bile osmolality were higher in patients with cholesterol gallstones than in controls without biliary tract disease. A correlation between the protein concentration and osmotic pressure was found in gallbladder patients but not in controls (patients: r = 0.83, P less than 0.05; controls: r = 0.74, P less than 0.1).

Bile concentration is a key factor for nucleation of cholesterol crystals and cholesterol saturation index in gallbladder bile of gallstone patients

We investigated whether bile concentration influenced cholesterol saturation index or nucleation time of cholesterol monohydrate crystals in a large number of gallbladder bile samples. Pigment stone patients never had cholesterol crystals in their fresh biles, and nucleation time was always longer than 20 days. Of the cholesterol stone patients 79% had cholesterol crystals in their fresh biles. Long nucleation times were generally found in cholesterol stone patients with dilute biles despite a high cholesterol saturation index. Nucleation time was usually short if bile was well concentrated despite a relatively low saturation index. Serial in vitro dilution of concentrated biles from cholesterol gallstone patients resulted in progressively prolonged nucleation times. Patients with solitary cholesterol stones had longer nucleation times than patients with multiple cholesterol stones. This study indicates that bile concentration is an important factor for nucleation time and cholesterol saturation index. Moreover, solitary and multiple cholesterol stones may have a different pathogenesis.

Application of reversed phase high performance liquid chromatography to the analysis of sulphidopeptide leukotrienes in pig bile

Reversed phase HPLC methodology has been developed for separation of peptide leukotrienes and indomethacin in porcine bile. Reproducible recoveries were obtained using radioactive leukotrienes ([3H]LTC4, 57.1 +/- 2.5%; [3H]LTE4, 62.7 +/- 1.9%; [3H]LTD4, 54.3 +/- 2.7%). Radioimmunoassay of column eluant demonstrated that as little as 300 pg of exogenous leukotrienes could be measured in bile fluids, with similar recoveries. Analysis of bile sampled 60-90 min after initiation of experimental endotoxic shock in indomethacin treated pigs revealed a leukotriene concentration of 5.24 +/- 1.16 ng/mL(LTD4). This was significantly greater (p less than 0.05, n = 3) than that observed in samples collected prior to endotoxin (0.42 +/- 0.23 ng/mL), or from untreated animals (0.85 +/- 0.51 ng/mL). This method is thus applicable to investigation of the role of 5-lipoxygenase products in porcine models of human disease, including shock conditions such as endotoxaemia, during cyclooxygenase inhibition by indomethacin.

[The correction of disorders of lipid-mineral composition of the bile as a method for preventing cholelithiasis]

A study is presented of the lipid and mineral metabolism composition in 60 patients with diseases of the biliary tract (dyskinesias, chronic noncalculous cholecystitis, cholelithiasis) before and after treatment with a hepatoprotective agent silibor, with a dry protein mixture containing amino acids and minerals and a vitamin-mineral agent quadevit. It was established that the patients showed disorders of the mineral and lipid composition of monotypical character but of different degrees of severity in those suffering of dyskinesias, cholecystitis and cholelithiasis. Silibor treatment furthered normalization of the lipid composition of bile, while treatment with dry protein mixture--of the mineral, with quadevit--of the lipid and mineral.

The effects of enteral stimulation on gallbladder bile during total parenteral nutrition in the neonatal piglet

The neonatal piglet is a satisfactory model for the human neonate requiring total parenteral nutrition (TPN). Bile status and subsequent liver and gallbladder dysfunction have long been documented as serious complications of long-term TPN. The purpose of this study was to determine whether small amounts of enteral formula during TPN will maintain normal bile appearance and composition. Thirty-one Hanford miniswine, 3 to 6 days old underwent surgery for the placement of central venous catheters. Two days postoperatively, the animals were separated into three groups, according to dietary regimens. Group 1 (n = 10), the control group, received pig formula (SPF-lac) orally (200 cal/kg/d); group 2 (n = 11), was maintained on TPN (180 cal/kg/d) with an enteral supplement of SPF-lac (20 cal/kg/d); group 3 (n = 10), was maintained on TPN only (200 cal/kg/d). The TPN formula consisted of 35 g/kg/d of glucose, 10 g/kg/d of protein, and 3 g/kg/d of lipid. The animals were maintained on these diets for 6 weeks. At necropsy, gallbladder with bile was weighed and bile volume and appearance was recorded. Chemical analyses was performed on 26 bile samples. Gallbladder weight was significantly decreased in groups 2 and 3 compared with group 1 (P less than .0003, P less than .033, respectively, using Students t test with Bonferoni adjustment). Volume was significantly decreased only in group 2 (P less than .003). Group differentiation in relation to bile appearance was determined by the presence or absence of either bile sludge or crystals.(ABSTRACT TRUNCATED AT 250 WORDS)

Bile acid composition in brown pigment stones

The bile acids in brown pigment stones and gallbladder bile were fractionated into free acids, glycine and taurine conjugates, and sulfates using diethylaminohydroxypropyl Sephadex LH-20 (DEAP-LH-20) column chromatography and were quantitated by gas chromatography. Twenty-eight cases of brown pigment stones were studied and divided into two groups: those with and those without bacteria possessing bile acid-deconjugating activity. In the former, free bile acid amounted to 62 +/- 34% of the total bile acid, while in the latter, only 0.1% of total bile acid was free bile acid. The fraction of total bile acid made up of free bile acids was found to be consistently higher in brown pigment stones than in the corresponding bile, irrespective of the presence or absence of biliary infection. Free bile acid is present in negligible amounts in normal bile. Total bile acid concentration in the bile of patients with brown pigment stones was significantly less than that of controls (13 vs 50 mg/ml). Biliary infection is almost always present in cases with brown pigment stones. These findings suggest that bacterial infection is present at the initiation of brown pigment stone formation as well as during the period of ensuing stone growth.

Quantitative ultrastructural studies of gall bladder epithelium in gall stone free subjects and patients with gall stones

The present study aimed at a further evaluation of the role of glycoproteins in the formation of cholesterol gall stones in man. An electron microscopic morphometric study of the gall bladder epithelium was performed in six gall stone free subjects and 12 gall stone patients. Six of the gall stone patients were treated with ursodeoxycholic acid three weeks before cholecystectomy. The number and the volume density of the mucin containing secretory granules, were not significantly increased in gall stone patients compared with gall stone free subjects. Treatment with ursodeoxycholic acid did not affect the number or volume density of the secretory granules. Thus, these results do not give evidence for that the degree of cholesterol saturation influences mucin content in the gall bladder wall of man. A major new finding was that gall stone patients had a markedly reduced total lysosome area and volume density of lysosomes compared with gall stone free subjects, a finding which may be related to a decreased intracellular degradation of protein and/or mucin.

Biliary lipid composition in monozygotic and dizygotic pairs of twins

The relative contribution of genetic factors to biliary and serum lipid composition was studied in 17 monozygotic and 18 dizygotic middle aged male pairs of twins. Cholesterol precursors, squalene and Methylated sterols which reflect the activity of cholesterol synthesis were also measured. Pairwise intraclass correlations were determined for monozygotic and dizygotic twin pairs and heritability estimates were calculated. Molar % of biliary cholesterol and percentage distribution of biliary cholic acid and particularly deoxycholic acid showed significant pairwise correlations within the monozygotic but not the dizygotic pairs. Similar correlations were found for total biliary methylsterols and of the methylsterol subfractions for the two methostenols but not for squalene, lanosterol and dimethylsterols. In serum, the precursor sterols, but not squalene, showed even higher pairwise correlations in the monozygotic twins than the corresponding precursors in bile. Molar per cent of bile acids and phospholipids and cholesterol saturation index were not correlated significantly in either twin pairs, but the pairwise correlations tended to be higher in the monozygotic than in the dizygotic pairs. Gall stones were found in seven monozygotic and three dizygotic subjects. Two monozygotic twin pairs were concordant for gall stones; all the dizygotic pairs were discordant. Overall, these data suggest that molar percentage of biliary cholesterol, bile acid composition, cholesterol synthesis, bile cholesterol saturation, and gall stone formation may be under a significant genetic control.

Identification of bile alcohols in rat bile

Bile alcohols in rat bile were analyzed by gas-liquid chromatography-mass spectrometry. Six bile alcohols were newly identified as minor constituents in addition to 5 beta-cholestane-3 alpha,7 alpha,12 alpha,26-tetrol, major bile alcohol of rat bile. The bile alcohols newly identified were 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol, 5 alpha-cholestane-3 alpha,7 alpha,12 alpha,26-tetrol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26-pentol, 5 alpha-cholestane-3 alpha,7 alpha,12 alpha,25,26-pentol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25,26-pentol, and 5 beta-cholestane-3 alpha,6 beta,7 beta,25,26-pentol. The biliary bile alcohols of the rat occurred mainly as the sulfuric acid esters and, in lesser amounts, as glucuronoconjugated and unconjugated forms. The amount of total bile alcohols was about 27.9 nmol in 1 ml of bile.

High-performance liquid chromatographic separation of bilirubin conjugates

A fast sensitive method for the isolation and quantitation of biliary bile pigments by reverse-phase high-performance liquid chromatography has been developed. Nine conjugates of bilirubin as well as unconjugated bilirubin and an internal standard, unconjugated mesobilirubin IX alpha, were all separated to baseline by gradient elution. The following sequence of eluted compounds was chemically identified by separating their ethyl anthranilate derivatives by thin-layer chromatography and by their enzymatic formation with UDP-bilirubin transferase and cosubstrate: bilirubin diglucuronide, bilirubin monoglucuronide monoglucoside, bilirubin monoglucuronide monoxyloside, bilirubin monoglucuronide (C-8, C-12), bilirubin diglucoside, bilirubin monoglucoside monoxyloside, bilirubin dixyloside, bilirubin monoglucoside (C-8, C-12), and bilirubin monoxyloside. The use of the commercially available mesobilirubin IX alpha as an internal standard was found to facilitate quantitation of the bilirubin conjugates.

[Changes in the phospholipid and prostaglandin levels in chronic diseases of the biliary tract]

A study of 179 patients with functional and organic diseases of the bile tract revealed that changes of the blood phospholipids and their spectra in the blood is observed at more early stages of the disease, functional pathology and that an increased PGE2/PGF2 indicates a deficit of polyunsaturated fatty acids and prevalence of the processes of break-up of prostaglandins over their synthesis.

The polymeric immunoglobulin A receptor is present on hepatocytes in human liver

A monoclonal antibody raised against human colostrum secretory component produced even staining of hepatocyte plasma membranes, as well as bile duct lining cells, in all sections examined from eight normal and three abnormal human livers. Human bile samples incubated with free secretory component degraded it to varying extents, probably proteolytically; true levels of free secretory component will therefore often be higher than those reported. It seems likely that human liver resembles that of other mammals in transferring polymeric IgA through hepatocytes to the bile by means of the polymeric IgA receptor.

[Polyunsaturated phosphatidylcholine and bile lipid composition]

The lipid composition of bile and the molar percentages of its components (cholesterol, lecithin [Lec], and bile salts) are influenced by diet composition (for example the content of cholesterol) and during fasting. Molecular species of Lec can be affected by the species of dietary fatty acids (a high n-3 fatty acid content in the diet increases their proportion in biliary Lec). The administration of polyunsaturated Lec (EPL), rich in 18:2-18:2-PC, increases the percentage of linoleic acid at position 2 of biliary lecithin, which is often reduced in subjects with cholesterol gallstones.