title: Characterization of endothelin receptors in the peripheral lung tissues of horses unaffected and affected with recurrent airway obstruction.
abstract: The purpose of the study was to determine and compare the expression of endothelin (ET) receptors in the peripheral lungs of healthy horses and those affected with recurrent airway obstruction (RAO) using reverse transcriptase polymerase chain reaction (RT-PCR), real-time PCR, Western blot analysis, and immunohistochemical techniques. Two groups of horses (7 healthy and 7 RAO-affected) were selected from a pool of horses destined for euthanasia. The grouping of horses was based on the history, clinical scoring, and pulmonary function testing. After euthanasia, gross postmortem evaluation of the lungs was conducted, and lung samples were collected and either stored at -80 degrees C or fixed in zinc-formalin for 12 h. The RT-PCR was performed by using specific primers for ETA and ETB receptors, and beta-actin. To determine the relative gene expression real-time PCR was performed. To detect ET receptor protein expression, Western blotting and immunohistochemical studies were performed using polyclonal antibodies against ETA and ETB receptors and beta-actin. The ET receptor expression was determined by performing either densitometric analyses or scoring of immunostaining. Statistical analyses were performed to detect differences in receptor expression within and between the 2 groups. The results indicated that ET receptor expression, particularly ETB receptors, was significantly greater in the peripheral lungs of RAO-affected horses than in those of healthy horses. Clinical trials using ET receptor antagonists, particularly ETB antagonists might help in developing a therapeutic strategy to treat this career-ending disease.
authors.affiliation: Equine Health Studies Program, Department of Comparative Biomedical Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803 USA.
authors.forename: Sumanth
authors.initials: S
authors.lastname: Polikepahad
authors.forename: Masudul
authors.initials: M
authors.lastname: Haque
authors.forename: Joseph
authors.initials: J
authors.lastname: Francis
authors.forename: Rustin M
authors.initials: RM
authors.lastname: Moore
authors.forename: Changaram S
authors.initials: CS
authors.lastname: Venugopal
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D016022:Case-Control Studies; D003720:Densitometry; D015870:Gene Expression; D006734:Horse Diseases / Q000378:metabolism*; D006736:Horses; D007150:Immunohistochemistry / Q000662:veterinary; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008173:Lung Diseases, Obstructive / Q000378:metabolism / Q000662:veterinary*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D017466:Receptors, Endothelin / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary
chemical_list: D017466:Receptors, Endothelin
references.citation: J Transl Med. 2004 May 27;2(1):16
references.pmid: 15165288
references.citation: Br J Pharmacol. 1996 Aug;118(8):1873-4
references.pmid: 8864516
references.citation: J Pharmacol Exp Ther. 1995 Dec;275(3):1084-9
references.pmid: 8531067
references.citation: Am J Vet Res. 2006 Feb;67(2):348-57
references.pmid: 16454644
references.citation: Can Vet J. 1992 Sep;33(9):591-8
references.pmid: 17424075
references.citation: J Biol Chem. 1994 Aug 26;269(34):21778-85
references.pmid: 7520443
references.citation: Pulm Pharmacol Ther. 1998 Apr-Jun;11(2-3):231-5
references.pmid: 9918762
references.citation: Mamm Genome. 1998 Apr;9(4):306-9
references.pmid: 9530628
references.citation: Am J Vet Res. 2000 Feb;61(2):167-73
references.pmid: 10685689
references.citation: J Pharmacol Exp Ther. 1996 Dec;279(3):1142-7
references.pmid: 8968335
references.citation: Histochem Cell Biol. 2002 Nov;118(5):361-9
references.pmid: 12432447
references.citation: Cell Tissue Res. 2005 Jan;319(1):103-19
references.pmid: 15503148
references.citation: Am J Physiol Lung Cell Mol Physiol. 2001 Apr;280(4):L659-65
references.pmid: 11238005
references.citation: Biochem Biophys Res Commun. 1994 Mar 30;199(3):1461-5
references.pmid: 8147891
references.citation: Am J Vet Res. 1997 Dec;58(12):1408-11
references.pmid: 9401689
references.citation: Can J Vet Res. 2006 Jan;70(1):50-7
references.pmid: 16548332
references.citation: Pharmacol Rev. 1994 Sep;46(3):325-415
references.pmid: 7831383
references.citation: Eur Respir J. 1996 Feb;9(2):351-5
references.pmid: 8777976
references.citation: J Am Vet Med Assoc. 1993 Mar 1;202(5):779-82
references.pmid: 8454516
references.citation: Am J Physiol Heart Circ Physiol. 2001 Feb;280(2):H777-85
references.pmid: 11158977
references.citation: Proc Natl Acad Sci U S A. 1988 Dec;85(24):9797-800
references.pmid: 3059352
references.citation: J Clin Invest. 1997 Sep 15;100(6):1448-58
references.pmid: 9294110
references.citation: Basic Clin Pharmacol Toxicol. 2004 Jul;95(1):43-8
references.pmid: 15245576
references.citation: Cell Tissue Res. 2002 Sep;309(3):381-6
references.pmid: 12195294
references.citation: Equine Vet J. 2003 Mar;35(2):190-6
references.pmid: 12638797
references.citation: Br Vet J. 1996 May;152(3):283-306
references.pmid: 8762605
references.citation: Thorax. 2001 Jan;56(1):30-5
references.pmid: 11120901
references.citation: Br J Pharmacol. 1995 Feb;114(3):563-9
references.pmid: 7735683
references.citation: Drug News Perspect. 1998 Sep;11(7):411-8
references.pmid: 15616682
references.citation: Eur J Pharmacol. 1999 Jan 15;365(1):R1-3
references.pmid: 9988131
references.citation: Hum Mol Genet. 1998 Jun;7(6):1047-52
references.pmid: 9580670
references.citation: Br J Pharmacol. 1998 Nov;125(5):963-8
references.pmid: 9846633
references.citation: Naunyn Schmiedebergs Arch Pharmacol. 2000 Aug;362(2):128-36
references.pmid: 10961375
references.citation: Br J Pharmacol. 1995 Jan;114(1):1-3
references.pmid: 7712003