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1.
Magnesium sulphate has previously been used as a purgative in a test involving the measurement of the faecal excretion of pancreatic enzymes. In order to validate the use of magnesium sulphate for this purpose, in 18 individuals the pancreatic and biliary response to intravenous infusion of secretin (1 CU/kg-h) plus CCK(1IU/kg-h) were compared with the responses to one of three dose-rates of magnesium sulphate infused into the duodenum. The effect of magnesium sulhphate was also studied during the coincident intravenous administration of the hormones. Intraduodenal magnesium sulphate did not stimulate the secretion of bicarbonate into the duodenum but did evoke the secretion of pancreatic enzymes and discharge of bile. The pancreatic response to the exogenous hormones was not altered by coincident intraduodenal infusion of magnesium sulphate. We conclude that magnesium sulphate is a satisfactory purgative for speeding the intestinal transit of pancreatic enzymes.  相似文献   

2.
The biliary and urinary excretion and the choleretic effect of ioglycamide were studied in unanesthetized bile fistula dogs using stepwise increasing infusion rates to obtain multiple steady states. The results are compared with data from previously reported experiments in the same animals using iodoxamate and iodipamide. The rate of biliary excretion and the choleretic effect of ioglycamide are similar to those of iodipamide and iodoxamate. Like iodipamide and iodoxamate, the relation between infusion rate or plasma concentration and biliary excretion or concentration of ioglycamide are hyperbolic and can be fitted to saturation kinetics. Quantitatively, the excretion of ioglycamide and iodipamide are virtually identical. However, for any equimolar infusion rate or plasma concentration, more iodoxamate than ioglycamide is excreted in the bile. Despite the greater biliary excretion of iodoxamate, the maximum biliary concentration of ioglycamide, iodipamide, and iodoxamate is the same at low basal bile flow because the choleretic effects of the three compounds are equal. The data suggest that, theoretically, with any equimolar dose ioglycamide will be identical to iodipamide as a contrast material for intravenous cholangiography, but that iodoxamate may be superior to ioglycamide because more iodoxamate is excreted in the bile. This advantage of iodoxamate might become apparent clinically in patients with high basal bile flow or if smaller doses of the contrast material are used. However, at the presently recommended doses of the two compounds, it is unlikely that the use of ioglycamide for intravenous cholangiography will be any different than iodoxamate.  相似文献   

3.
The rate of excretion of aldosterone radiometabolites into the bile duct cannulation, and the intravenous injection of (3H)aldosterone, was demonstrated to be markedly increased in male rats following castration. In 1 h, 72% of the injected 3H-radioactivity was excreted in the bile of castrated male rats compared with 26% in the intact male control rats. Castration of the males led to the increased biliary excretion of aldosterone metabolites and the elimination of the sex-dependence of this process in rats. The ovariectomy of female rats did not substantially increase the rate of excretion of aldosterone metabolites via the bile. Castrated male rats treated with testosterone excreted aldosterone metabolites into the bile at a slower rate. A similar treatment of ovariectomized female rats with testosterone also significantly slowed the rate of biliary excretion of the aldosterone metabolites. These findings suggest that the presence of androgens plays an important role in regulating the routes of hepatic metabolism of aldosterone and the rates of clearance of aldosterone and its metabolites from the plasma into the bile of rats.  相似文献   

4.
The biliary excretion of the four isomers of bilirubin-IX was studied in Wistar rats (JJ) and homozygous Gunn rats (jj). Synthetic preparations of 14C-labelled pigments were used. 1. After intravenous administration, the alpha-isomer was rapidly excreted in conjugated form in bile of Wistar rats. In Gunn rats excretion was insignificant. In contrast, both rat species promptly excreted the non-alpha-isomers at rates that were comparable with that found for bilirubin-IXalpha in Wistar rats. 2. In normal rats about 16% of the beta- and delta-isomers and at least 50% of the gamma-isomer were excreted as ester conjugates of the injected parent bile pigments. Conjugation of the beta- and delta-isomers had occurred exclusively at the carboxyl groups of pyrrole ring D and C respectively. For bilirubin-IXgamma no preference for any carboxyl group could be established. 3. In homozygous Gunn rats the non-alpha-isomers were apparently excreted chemically unaltered. This suggests that, as for bilirubin-IXalpha, conjugation of the non-alpha-isomers is also deficient in Gunn rats.  相似文献   

5.
The excretion of 58Co2+ via bile, urine and intestinal wall after intravenous administration of 58CoCl2 in two doses (177 and 1770 micrograms of Co2+ per kg B. Wt.) was studied in rats. The cumulative biliary excretion reached 24 hours after administration of lower dose 2.67 +/- 1.98% and higher dose 7.33 (4.6-10.9) % of the amount given. The highest excretion rate of 58Co was detected between 10 and 30 minutes after administration. After administration of higher dose of 58Co the lower urinary excretion was observed [73.6 +/- 4.0% resp. 47.9% (45.5-52.5)] of the amount given. There were no differences between both doses studied in the excretion of 58Co via the wall of gastrointestinal tract.  相似文献   

6.
Alcohol has been reported to increase the urinary excretion of dolichols, and urinary dolichols are suggested to be derived from the lysosomes of the renal cells. In the present study we examined the effects of alcohol and glucagon on the biliary excretion of dolichols in rats. Chronic ethanol treatment decreased both biliary dolichol and beta-hexosaminidase excretion. The absolute amount of dolichol excreted into the bile correlated highly significantly with the absolute amount of biliary beta-hexosaminidase. Our results indicate that biliary dolichols are--at least in part--derived from hepatic lysosomes. Decreased biliary dolichol output during chronic alcohol administration suggests that urinary and biliary dolichol excretions are regulated independently of each other.  相似文献   

7.
The absorption, concentrations in plasma, metabolism and excretion of ramatroban ((+)-(3R)-3-(4-fluorophenylsulfonamido)-1,2,3,4-tetrahydro-9- carbazolepropanoic acid, CAS 116649-85-5, BAY u 3405) have been studied following a single intravenous, oral, or intraduodenal administration of 14C-labeled or nonlabeled compound to rats and dogs (dose range: 1-10 mg.kg-1). After intraduodenal administration of [14C]ramatroban, enteral absorption of radioactivity was rapid and almost complete both in bile duct-cannulated male rats (83%) and female dogs (95%). The oral bioavailability of ramatroban was complete in the dog but amounted to about 50% in the rat due to presystemic elimination. A marked food effect on the rate but not on the extent of absorption was observed in rats. The elimination of the parent compound from plasma occurred rapidly with total clearance of 1.2 l.h-1.kg-1 in male rats and 0.7 l.h-1.kg-1 in dogs. After oral administration to male rats AUC increased dose-proportionally between 1 and 10 mg.kg-1, whereas in Cmax an over-proportional increase was observed. Excretion of total radioactivity was fast and occurred predominantly via the biliary/fecal route in both species. The residues were low, 144 h after dosing less than 0.2% of the radioactivity remained in the body of rats. A considerable sex difference was found in rats following oral administration of ramatroban. In females a 3-fold higher AUC and a 1.7-fold longer half-life of unchanged compound, as well as 3-fold higher renal excretion of total radioactivity was observed. A marked species difference exists in the metabolism of ramatroban. In dogs the drug was almost exclusively metabolized via conjugation with glucuronic acid, whereas in rats oxidative phase I metabolism and glucuronidation were equally important. As a consequence enterohepatic circulation was much more pronounced in dogs (77%) than in rats (17% of the initial dose).  相似文献   

8.
BACKGROUND/AIMS: Liver reperfusion following cold ischemia is frequently associated with diminished bile flow in patients undergoing liver transplantation. Glutathione is a major determinant of bile-acid independent bile flow, and the effects of cold ischemia on biliary glutathione excretion are unknown. METHODS: We examined the effects of cold ischemia (University of Wisconsin solution (4 degrees C), 24 h) with subsequent reperfusion (100 min) on biliary glutathione excretion in a recirculating system. Since glutathione might represent an important antioxidant within the biliary tract and oxidative stress in the biliary tract during reperfusion could contribute to the pathogenesis of bile duct injury after liver transplantation, we also assessed bile duct morphology in reperfused livers of mutant TR- -rats, in whom biliary excretion of glutathione is already impaired. RESULTS: Hepatic bile formation was diminished in reperfused Wistar rat livers after cold ischemia. Biliary glutathione concentrations and output were significantly decreased and correlated with postischemic changes in bile secretion. An increased biliary oxidized glutathione/glutathione ratio, indicating oxidative stress, was detected only immediately after the onset of reperfusion. Basal bile flow rates in TR- -rat livers which were already markedly reduced in control-perfused livers, decreased further during the early but not the later reperfusion period. Reperfusion of both Wistar and TR- -rat livers was not associated with electron microscopic evidence of bile duct damage. CONCLUSIONS: We conclude that impaired biliary excretion of glutathione contributes to decreased bile flow after cold ischemia. The absence of biliary glutathione does not appear to promote ultrastructural evidence of bile duct injury during reperfusion in the isolated perfused rat liver.  相似文献   

9.
The distribution of ceftezole in blood and tissues and its excretion after intramuscular or intravenous administration of single doses of 10 and 20 mg/kg were compared with those of cefazolin, cephaloridine and cephalothin. Blood levels of ceftezole in rats and rabbits were lower than those of cefazolin, and higher than those of cephaloridine and cephalothin. Retention time of ceftezole in the blood was somewhat shorter than that of cefazolin. However, blood levels of ceftezole in dogs were nearly the same as those of cefazolin and cephaloridine. The rate of urinary excretion of ceftezole in 24-hour urine after administration in rats and rabbits was found to be higher than those of the other antibiotics tested. In dogs, however, the rate of urinary excretion of ceftezole was nearly the same as that of cefazolin and higher than those of cephaloridine and cephalothin. The biliary excretion of ceftezole in rats and dogs was much higher than those of cephaloridine and cephalothin, but lower than that of cefazolin. Tissue distribution of ceftezole in rats was compared with that of the other antibiotics by intramuscular and intravenous administration. The initial level of ceftezole in the kidneys was found to be substantially higher than those of the other antibiotics. The initial level of ceftezole in the liver and lungs was also slightly higher than those of the other drugs when administered intramuscularly. Tissue levels of ceftezole were somewhat lower than those of cefazolin in rabbits after intravenous administration. Ceftezole attained a higher maximum level in rat lymph by intramuscular administration than the other antibiotics tested. The maximum concentration of ceftezole present in the exudate in the rat inflammatory pouch was higher than that of cefazolin. In rabbits with cerebrospinal meningitis induced by infection of Streptococcus pyogenes, the level of ceftezole in the cerebrospinal fluid was several times higher than that in normal rabbits. The serum level and urinary excretion of ceftezole was examined in 6 healthy male volunteers after intramuscular administration of a single dose of 500 mg. Ceftezole attained a mean maximum serum level of 22.9 mug/ml 30 minutes after administration and disappeared from the blood in about 6 hours. It was excreted rapidly in the urine. The concentration in 1-hour urine was the highest (mean level: 2,667 mug/ml) and the total excretion rate was 92.6%. No metabolites with antimicrobial activity were observed in the urine. No changes in the pattern of plasma level and urinary excretion and no accumulation in the tissues were observed after repeated intramuscular administration of 20 mg/kg of ceftezole in rabbits, 26 times, for 14 days.  相似文献   

10.
Examination was made of the urinary and biliary excretion of the metabolites of genistein and genistein, the major components of Glycine and Sophora genus in rats. The urine of rats administered genistein orally contained eight metabolites. Three of these metabolites, genistein 4'-O-sulfate (M-1), genistein 7-O-beta-D-glucuronide (M-3), genistein 4'-O-sulfate 7-O-beta-D-glucuronide (M-6), were identified from spectroscopic and chemical data. The bile of rats administered genistein orally contained M-2, M-3 and M-6. M-6, a major biliary metabolite, was isolated and identified from spectroscopic and chemical data. The urine or bile of rats treated with genistein, the glycoside of genistein, contained M-1-M-8 or M-2, M-3, M-6 in the above metabolites. These findings suggest that genistein is absorbed as genistein after hydrolysis in the gastrointestinal tract. The total cumulative amounts of the two metabolites and genistein excreted in the urine during 48h, or of M-6 excreted in the bile during 36h following the oral administration of genistein, were approximately 5.7% or 16.0% of the doses administered, respectively. The result show that M-1, M-3 and M-6, having a free hydroxyl, glucuronide- or sulfate-conjugated hydroxyls at the C-7 or C-4' position, are excreted in the urine and bile as parts of the metabolites of genistein.  相似文献   

11.
The effect of isoniazid (0,10,20 and 40 mg/kg; i.v.) on the biliary and urinary excretion of [14C] diphenylhydantoin (DPH, 50 mg/kg; i.v.) was investigated in biliary-fistulated rats during the first 5 hours. Isoniazid cause a dose-dependent reduction in the total biliary excretion of 14 C without affecting its output in urine. After 5 h, maximal levels of radioactivity were recorded in the liver, followed by heart and brain. The glucuronides of DPH metabolites accounted for most of the 14C in 5 h pooled bile, less than 1% of the injected dose was excreted as unmetabolized DPH. Isoniazid administration caused the following significant dose-related changes in biliary excretion: (a) increased excretion of the unconjugated principal DPH metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantion (HPPH); (b) decreased excretion of HPPH-glucuronide; and (c) increased excretion of the glucuronide conjugates of the polar metabolites of DPH. The results suggest that the isoniazid-induced elevation of DPH-derived 14C in blood and its marked accumulation in brain, heart and liver is due to inhibition of p-hydroxylation of DPH and the glucuronidation of HPPH.  相似文献   

12.
Cholestatic jaundice is the major complication of total parenteral nutrition (TPN). Both the intravenous (IV) route of nutrition and the enteral fast have been implicated as causes of TPN-associated cholestasis (TPN-AC). The purpose of this study was to determine whether TPN-AC is caused by the TPN solution itself or the IV route of administration and enteral fast. Prepubescent rabbits (n = 24) were divided into four groups: CONTROL, fed standard lab chow; TPN, received a standard hyperalimentation solution of dextrose, Aminosyn, and lipids via the jugular vein; ENT, received the same hyperalimentation solution via a duodenostomy tube; and OSM, received a polymeric formula (Osmolite) via a duodenostomy tube. After 14 days on these diets, we measured bile flow, bile acid excretion, sulfobromophthalein (BSP) excretion, plasma amino acid profile, serum liver enzymes, and liver histology. Statistical analysis was by analysis of variance. Hyperalimentation solution significantly depressed hepatobiliary function, whether it was given IV or by gut. Bile flow in both the TPN (36.4 microL/kg/min) and ENT (46.2) groups was significantly less than CONTROL (84.5) or OSM (62.9). Hepatic secretory function, measured by excretion of the cholephilic dye BSP, was depressed in both TPN and ENT (57% and 55% of IV dose excreted in bile over 60 minutes, respectively) compared with CONTROL (84%) or OSM (71%). Serum liver enzymes were normal in all groups. Histological injury similar to TPN-AC in humans (portal inflammation and hepatocyte degeneration) was seen in both groups receiving the hyperalimentation solution.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
The intestinal absorption, biliary excretion and metabolism of genistein, a potent and specific protein tyrosine kinase inhibitor that occurs naturally in soy foods, was examined in anesthetized, adult female rats fitted with indwelling biliary cannulas. 4-14C-Genistein, when infused into the duodenum, was rapidly absorbed from the intestine, taken up by the liver and excreted into the bile as its 7-O-beta-glucuronide conjugate. Cumulative recovery of 14C-radioactivity in the bile over a 4-h period was 70-75% of the dose. When genistein was infused into the portal vein, it was also taken up efficiently by the liver, conjugated with glucuronic acid and transported into bile. However, portal blood collected after duodenal infusions of genistein contained mostly genistein 7-O-beta-glucuronide, suggesting that in vivo glucuronidation occurred in the intestinal wall rather than the liver. This was confirmed using everted intestinal sac preparations. Reinfusion of genistein 7-O-beta-glucuronide into the duodenum or into the mid small intestine resulted in its reappearance in the bile, albeit more slowly than when genistein was infused. Over a 4-h collection period, the cumulative recovery of 14C-radioactivity in bile was 27 and 70-75% of the administered dose for duodenal and ileal infusions, respectively. These data indicate that genistein is highly bioavailable in rats and because of its enterohepatic circulation may accumulate within the gastrointestinal tract.  相似文献   

14.
Levels of cefazolin were determined in plasma, urine, bile, and cerebrospinal fluid in humans after a bolus intravenous injection and during a controlled, continuous intravenous infusion. All the patients were studied in a steady-state and crossover fashion. In plasma, the mean peak level after bolus injection (1.5 g) studied in 12 patients was 206.5 mug/ml; during continuous infusion (6 g daily), the mean level remained stable at 52.6 mug/ml. With bolus injection and continuous infusion, respectively, 89.7 and 86.3% of the administered dose of cefazolin were excreted in the urine of nine patients over the 6-h period considered. The levels of cefazolin in common bile duct bile were studied in six cholecystectomized patients. In bile collected during the two 3-h periods of the experiment, the mean concentration of the drug in the bile after bolus injection was 66.9 and 22.0 mug/ml, respectively; during continuous infusion, the corresponding biliary levels were 50.7 and 51.3 mug/ml, respectively. In four neurosurgical patients with an intraventricular catheter, neither bolus injection nor continuous infusion resulted in a demonstrable concentration of cefazolin in the cerebrospinal fluid. The continuous intravenous administration of cefazolin might have some advantage over the intravenous bolus intermittent injections. In plasma, the area under the curve is greater with continuous infusion than with bolus injection. In bile, the levels of cefazolin are more sustained with continuous infusion than with bolus injection. This approach to intravenous administration of cefazolin deserves more pharmacological and clinical trials.  相似文献   

15.
The significance of bile as an excretory route for cadmium (Cd) was studied in anesthetized, bile-duct-cannulated Sprague-Dawley rats during a 6-hr collection period. Observations were made on bile flow rates, the concentrations of Cd in bile following dietary and parenteral Cd exposure, and the influences of zinc (Zn), selenium (Se), and Cd pretreatments upon the biliary excretion of subsequently administered Cd. The bile flow rates ranged between 1.96 and 2.89 mg/g rat-hr (22 +/- 3 ppb Cd) for normal rats and between 2.68 and 4.09 mg/g rat-hr (58 +/- 6 ppb Cd) for rats fed 100 ppm Cd. Less than 0.1% of the Cd administered subcutaneously at rates ranging from 0.25 to 40 mg/kg rat could be accounted for in bile collected during the 5-hr period following the parenteral Cd injections. Subcutaneous administration of 8 mg Zn/kg rat or 0.5 mg Cd/kg rat on days 1 and 6, respectively, before the postcannulation administration of 1 mg Cd/kg rat caused a significant reduction in the biliary excretion of Cd during the bile collection period. Administering 2 mg Se/kg rat 3 days prior to the postcannulation administration of 1 mg Cd/kg rat caused a significant increase in the biliary excretion of Cd during the bile collection period. The biochemical bases for these observations are believed associated with the type of metal-binding protein induced by the respective pretreatments.  相似文献   

16.
HSR-903 is a newly synthesized quinolone antibacterial agent with low toxicity. The biliary and urinary excretion of unchanged HSR-903, its R-isomer, and their glucuronides was determined after iv bolus administration (5 mg/kg) to normal Sprague-Dawley rats (SDR) and Eisai hyperbilirubinemic mutant rats (EHBR). The values for the biliary excretion clearance of HSR-903 and its glucuronide in EHBR were decreased to approximately 40 and 2% of those in SDR, respectively, whereas the values for the urinary excretion clearance of HSR-903 and its glucuronide were comparable in SDR and EHBR. The biliary excretion clearance values for the R-isomer and its glucuronide were approximately 3 times greater than those for HSR-903. These results demonstrated that the enantiomers of HSR-903 and their conjugates were excreted into bile in a stereospecific manner. The hepatic uptake of [14C]HSR-903 in vivo was evaluated by means of integration plot analysis. The results indicated that the hepatic uptake of [14C]HSR-903 was very fast and was blood flow-limited. To clarify the mechanism of excretion of HSR-903 into bile, the uptake and efflux of [14C]HSR-903 were studied using isolated hepatocytes from SDR and EHBR. The initial uptake of HSR-903 by hepatocytes was temperature-dependent, saturable, and stereospecific. Unlabeled HSR-903 (S-isomer), the R-isomer, grepafloxacin, and sparfloxacin significantly inhibited the uptake of [14C]HSR-903. The efflux of [14C]HSR-903 from hepatocytes from EHBR was significantly slower than that from hepatocytes from SDR. The addition of sodium azide or bromosulfophthalein reduced the efflux of [14C]HSR-903. These results demonstrate that HSR-903 is actively excreted into bile via the canalicular multispecific organic anion transporter, which is deficient in EHBR.  相似文献   

17.
A new HPLC assay was adapted for radiometric detection of nicotine metabolites in rat bile. Two glucuronides were identified as the principal biliary metabolites of nicotine. In addition to nicotine glucuronide and 3-hydroxycotinine glucuronide, cotinine was also detected in bile after administration to rats of a single subcutaneous dose of (-)-S-nicotine (0.2 or 1.0 mg/kg) that contained a tracer dose of rac-[pyrrolidine-2'-14C]nicotine (20 microCi). Biliary metabolites accounted for only 3% of the [14C]nicotine dose, but phenobarbital pretreatment (100 mg/kg ip for 3 days) increased the amount of [14C]nicotine-derived radioactivity recovered in bile to 8% and also accelerated rates of biliary excretion of all three nicotine metabolites. Dose-dependency of nicotine metabolism occurred: less nicotine glucuronide was excreted at the low dose than at the high dose.  相似文献   

18.
The results demonstrate the biliary reabsorption of 14C-cholate, 14C-glycocholate, and 14C-taurocholate from the rat biliary tree after retrograde intrabiliary injection. It could be shown that retrograde injection of these bile salts (20 nmol) in a total volume of 40 mul leads to significantly increased biliary reabsorption in contrast to the administration in a retrograde volume of only 20 mul. These differences in reabsorption may be explained by greater reabsorption at a more proximal site in the biliary tree. Furthermore 14C-glycocholate and 14C-taurocholate are reabsorbed to a lesser extent in contrast to 14C-cholate when bile flow was restarted at once after retrograde injection in a volume of 40 mul. It is speculated that conjugation of cholate to glycine and taurine has some effect on the extent of biliary reabsorption of this bile acid. Following the results presented in this paper one might hypothize that biliary reabsorption has an important influence on bile composition i.e. the biliary excretion of bile salts.  相似文献   

19.
We have recently reported that endotoxin (lipopolysaccharide [LPS]) derived from Klebsiella pneumoniae dramatically decreased the biliary excretion of the beta-lactam antibiotic cefoperazone (CPZ), which is primarily excreted into the bile via the anion transport system, in rats. The present study was designed to investigate the effect of human recombinant granulocyte colony-stimulating factor (G-CSF), which is reported to be beneficial in experimental models of inflammation, on the pharmacokinetics and biliary excretion of CPZ in rats. CPZ (20 mg/kg of body weight) was administered intravenously 2 h after the intravenous injection of LPS (250 microgram/kg). G-CSF was injected subcutaneously at 12 microgram/kg for 3 days and was administered intravenously at a final dose of 50 microgram/kg 1 h before LPS injection. Peripheral blood cell numbers were also measured. LPS dramatically decreased the systemic and biliary clearances of CPZ and the bile flow rate. Pretreatment with G-CSF enhanced these decreases induced by LPS. The total leukocyte numbers were increased in rats pretreated with G-CSF compared to the numbers in the controls, while the total leukocyte numbers were decreased (about 3,000 cells/microliter) by treatment with LPS. Pretreatment with G-CSF produces a deleterious effect against the LPS-induced decrease in biliary secretion of CPZ, and leukocytes play an important role in that mechanism.  相似文献   

20.
The effect of the administration route, dose, and sampling time on the total urinary excretion of four major benzo[a]pyrene (BaP) metabolites, 3-hydroxyBaP (3-OHBaP), 9-hydroxyBaP 9-hydroxyBaP (9-OHBaP), trans-4,5-dihydrodiolBaP (4,5-diolBaP), and trans-9,10-dihydrodiolBaP (9,10-diolBaP), was studied in male Sprague-Dawley rats exposed to a single intravenous, oral, and cutaneous dose of 2, 6, 20, and 60 mumol BaP/kg. Urine samples were collected at 24-h intervals following treatment. Over the 0-72 h period and for a given dose, amounts of BaP metabolites were 3-OHBaP > 4,5-diolBaP > > 9-OHBaP following intravenous and oral dosing, and 3-OHBaP > > 9-OHBaP > or = 4,5-diolBaP after cutaneous treatment. 9,10-diolBaP was barely detected. On the other hand, amounts of 3-OHBaP and 4,5-diolBaP excreted in urine over the 0-72 h period and for a given dose appeared in the following order: intravenous approximately oral > or = cutaneous. Amounts of 9-OHBaP excreted varied as follows: oral > or = cutaneous > intravenous. For all routes of administration, excretion of 4,5-diolBaP was almost complete over the 0-24 h period in contrast with 3-OHBaP and 9-OHBaP. Peak excretion of 3-OHBaP and 9-OHBaP was reached in the 0-24 h period following intravenous and oral treatment and in the 24-48 h period following cutaneous application. Overall, for a given administration route and dose, there were variations in the time profiles between metabolites. In general, there was nonetheless a good correlation between the BaP dose and urinary excretion of 3-OHBaP, 9-OHBaP, and 4,5-diolBaP. Furthermore, total urinary excretion of a specific metabolite, its time profile, and the relative proportion of the metabolites studied depended on the administration route. Data also suggest that a measure of the concentration ratio of the different metabolites could reflect the time and main route of exposure.  相似文献   

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