Hepatic uptake of fluorescein, investigated by video fluorescence microscopy and digital image analysis

Schmidt, Regina; Buscher, Hans-Peter

doi:10.1016/0168-8278(91)90816-t

Cited by 6 publications

(5 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, during the first minute of perfusion, cholyltaurine uptake exceeded that of cholylglycine. Fluorescein, whose uptake by the hepatocyte is considered to occur passively without involvement of a carrier, 28 had the lowest first-pass extraction of any of the compounds (68%). Fractional extraction at 15 minutes declined for all fluorescent bile acids, mostly because of regurgitation.…”

Section: Resultsmentioning

confidence: 99%

“…Of course, molecules that regurgitate from a periportal hepatocyte will be taken up by the pericentral cells; thus, the process of uptake and regurgitation continues along the entire hepatic lobule. 35 Regurgitation that is non-carrier-mediated can also explain in part the similar time-dependent decrease in net fractional extraction of fluorescein and norUDCA, because both fluorescein 28 and norUDCA (based on the properties of its epimer norchenodeoxycholic acid 37 ) are thought to be highly permeable to cell membranes and should regurgitate from the hepatocyte when their intracellular (unbound) concentration exceeds that in the perfusate. Such regurgitation has been shown previously for nordeoxycholic acid, 38 a molecule that should be handled by the basolateral membrane of the hepatocyte in a manner similar to that of norUDCA.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Transport of fluorescent bile acids by the isolated perfused rat liver: Kinetics, sequestration, and mobilization

et al. 1998

View full text Add to dashboard Cite

Hepatocyte transport of six fluorescent bile acids containing nitrobenzoxadiazolyl (NBD) or a fluorescein derivative on the side chain was compared with that of natural bile acids using the single-pass perfused rat liver. Compounds were infused at 40 nmol/g liver min for 15 minutes; hepatic uptake and biliary recovery were measured; fractional extraction, intrinsic basolateral clearance, and sequestration (nonrecovery after 45 minutes of additional perfusion) were calculated. Fluorescent bile acids were efficiently extracted during the first 3 minutes (70%-97%), but net extraction decreased with time mostly because of regurgitation into the perfusate. For cholylglycine and ursodeoxycholylglycine (UDC-glycine), extraction was 94% to 99%, and regurgitation did not occur. Intrinsic hepatic clearance of fluorescent bile acids (2-7 mL/g liver x min) was lower than that of cholylglycine (9.0 +/- 0.6; mean +/- SD) and UDC-glycine (21.4 +/- 0.4). Sequestration at 60 minutes was 8% to 26% for fluorescent bile acids with a cholyl moiety (cholylglycylaminofluorescein [CGamF], cholyllysylfluorescein [C-L-F], cholyl-[N epsilon-NBD]-lysine [C-L-NBD], and cholylaminofluorescein [CamF]), 32% for ursodeoxycholylaminofluorescein (UDCamF), and 88% for ursodeoxycholyl-(N epsilon-NBD)lysine (UDC-L-NBD). Cholylglycine and UDC-glycine had <3% retention. Biliary secretion of sequestered UDCamF, but not of UDC-L-NBD, was induced by adding dibutyryl cyclic adenosine monophosphate (DBcAMP) to the perfusate, possibly by translocation to the canaliculus of pericanalicular vesicles containing fluorescent bile acids. Biliary secretion of UDC-L-NBD, but not of UDCamF, was induced by adding cholyltaurine or UDC-taurine, possibly by inhibition of binding to intracellular constituents or of transport into organelles. It is concluded that fluorescent bile acids are efficiently transported across the basolateral membrane, but in contrast to natural conjugated bile acids, are sequestered in the hepatocyte (UDC derivatives > cholyl derivatives). Two modes of hepatic sequestration of fluorescent bile acids were identified. Fluorescent bile acids may be useful to characterize sequestration processes during bile acid transport through the hepatocyte.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Transport of fluorescent bile acids by the isolated perfused rat liver: Kinetics, sequestration, and mobilization

et al. 1998

View full text Add to dashboard Cite

show abstract

“…Even in bright field pictures (Additional file 1) yellow staining of fluorescein can be seen in the gallbladder. Therefore, the fate of fluorescein in older medaka embryos is comparable to that of mammals [19]. …”

Section: Resultsmentioning

confidence: 99%

Diffusion of small molecules into medaka embryos improved by electroporation

et al. 2013

View full text Add to dashboard Cite

BackgroundDiffusion of small molecules into fish embryos is essential for many experimental procedures in developmental biology and toxicology. Since we observed a weak uptake of lithium into medaka eggs we started a detailed analysis of its diffusion properties using small fluorescent molecules.ResultsContrary to our expectations, not the rigid outer chorion but instead membrane systems surrounding the embryo/yolk turned out to be the limiting factor for diffusion into medaka eggs. The consequence is a bi-phasic uptake of small molecules first reaching the pervitelline space with a diffusion half-time in the range of a few minutes. This is followed by a slow second phase (half-time in the range of several hours) during which accumulation in the embryo/yolk takes place. Treatment with detergents improved the uptake, but strongly affected the internal distribution of the molecules. Testing electroporation we could establish conditions to overcome the diffusion barrier. Applying this method to lithium chloride we observed anterior truncations in medaka embryos in agreement with its proposed activation of Wnt signalling.ConclusionsThe diffusion of small molecules into medaka embryos is slow, caused by membrane systems underneath the chorion. These results have important implications for pharmacologic/toxicologic techniques like the fish embryo test, which therefore require extended incubation times in order to reach sufficient concentrations in the embryos.

show abstract

“…Another fluorescent bile acid, cholyllysylfluorescein, has been shown to have transport properties similar to those of CGF [6]; therefore, this fluorescent bile acid should, at least in principle, also be suitable for the application described here [8]. For visualizing the bifiary tree, fluorescent bile acids appear to be superior to fluorescein because fluorescent bile acids will enter only those cells that have a suitable anion transporter, such as the hepatocyte, whereas fluorescein enters all cells by passive diffusion [12].…”

Section: Discussionmentioning

confidence: 99%

Use of a fluorescent bile acid to enhance visualization of the biliary tract and bile leaks during laparoscopic surgery in rabbits

et al. 2001

View full text Add to dashboard Cite

show abstract

Hepatic uptake of fluorescein, investigated by video fluorescence microscopy and digital image analysis

Cited by 6 publications

References 5 publications

Transport of fluorescent bile acids by the isolated perfused rat liver: Kinetics, sequestration, and mobilization

Transport of fluorescent bile acids by the isolated perfused rat liver: Kinetics, sequestration, and mobilization

Diffusion of small molecules into medaka embryos improved by electroporation

Use of a fluorescent bile acid to enhance visualization of the biliary tract and bile leaks during laparoscopic surgery in rabbits

Contact Info

Product

Resources

About