![]() |
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Departments of Surgery (G.P.L., M.K.M.) and Radiology (R.W.P.) and McArdle Laboratory for Cancer Research (E.G., H.C.P., C.A.B.), University of Wisconsin Medical School, Madison, Wisconsin
Abstract
A developmental role for the Ahr locus has been indicated by the observation that mice harboring a null allele display a portocaval vascular shunt throughout life. To define the ontogeny and determine the identity of this shunt, we developed a visualization approach in which three-dimensional (3D) images of the developing liver vasculature are generated from serial sections. Applying this 3D visualization approach at multiple developmental times allowed us to demonstrate that the portocaval shunt observed in Ahr-null mice is the remnant of an embryonic structure and is not acquired after birth. We observed that the shunt is found in late-stage wild-type embryos but closes during the first 48 h of postnatal life. In contrast, the same structure fails to close in Ahr-null mice and remains open throughout adulthood. The ontogeny of this shunt, along with its 3D position, allowed us to conclude that this shunt is a patent developmental structure known as the ductus venosus (DV). Upon searching for a physiological cause of the patent DV, we observed that during the first 48 h, most major hepatic veins, such as the portal and umbilical veins, normally decrease in diameter but do not change in Ahr-null mice. This observation suggests that failure of the DV to close may be the consequence of increased blood pressure or a failure in vasoconstriction in the developing liver.
Address correspondence to: Christopher A. Bradfield, McArdle Laboratory for Cancer Research, 1400 University Ave., Madison, WI 53706. E-mail: bradfield{at}oncology.wisc.edu
This article has been cited by other articles:
![]() |
M. Mukai, T.-M. Lin, R. E. Peterson, P. S. Cooke, and S. A. Tischkau Behavioral Rhythmicity of Mice Lacking AhR and Attenuation of Light-Induced Phase Shift by 2,3,7,8-Tetrachlorodibenzo-p-Dioxin J Biol Rhythms, June 1, 2008; 23(3): 200 - 210. [Abstract] [PDF] |
||||
![]() |
N. Dragin, Z. Shi, R. Madan, C. L. Karp, M. A. Sartor, C. Chen, F. J. Gonzalez, and D. W. Nebert Phenotype of the Cyp1a1/1a2/1b1(-/-) Triple-Knockout Mouse Mol. Pharmacol., June 1, 2008; 73(6): 1844 - 1856. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. J. McMillan and C. A. Bradfield The Aryl Hydrocarbon Receptor sans Xenobiotics: Endogenous Function in Genetic Model Systems Mol. Pharmacol., September 1, 2007; 72(3): 487 - 498. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. B. Okey An Aryl Hydrocarbon Receptor Odyssey to the Shores of Toxicology: The Deichmann Lecture, International Congress of Toxicology-XI Toxicol. Sci., July 1, 2007; 98(1): 5 - 38. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. A. Fritz, T.-M. Lin, R. D. Cardiff, and R. E. Peterson The aryl hydrocarbon receptor inhibits prostate carcinogenesis in TRAMP mice Carcinogenesis, February 1, 2007; 28(2): 497 - 505. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. J. McMillan and C. A. Bradfield The Aryl hydrocarbon receptor is activated by modified low-density lipoprotein PNAS, January 23, 2007; 104(4): 1412 - 1417. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Dragin, T. P. Dalton, M. L. Miller, H. G. Shertzer, and D. W. Nebert For Dioxin-induced Birth Defects, Mouse or Human CYP1A2 in Maternal Liver Protects whereas Mouse CYP1A1 and CYP1B1 Are Inconsequential J. Biol. Chem., July 7, 2006; 281(27): 18591 - 18600. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. E. Dunham, E. A. Stevens, E. Glover, and C. A. Bradfield The Aryl Hydrocarbon Receptor Signaling Pathway Is Modified through Interactions with a Kelch Protein Mol. Pharmacol., July 1, 2006; 70(1): 8 - 15. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Mulero-Navarro, J.M. Carvajal-Gonzalez, M. Herranz, E. Ballestar, M.F. Fraga, S. Ropero, M. Esteller, and P.M. Fernandez-Salguero The dioxin receptor is silenced by promoter hypermethylation in human acute lymphoblastic leukemia through inhibition of Sp1 binding Carcinogenesis, May 1, 2006; 27(5): 1099 - 1104. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. B. Harstad, C. A. Guite, T. L. Thomae, and C. A. Bradfield Liver Deformation in Ahr-Null Mice: Evidence for Aberrant Hepatic Perfusion In Early Development Mol. Pharmacol., May 1, 2006; 69(5): 1534 - 1541. [Abstract] [Full Text] [PDF] |
||||