Down‐regulation of vascular α1‐adrenoceptors does not account for the loss of vascular responsiveness to catecholamines in experimental cholestasis

Wiley - Tập 19 Số 3 - Trang 193-198 - 1999
Kamal Dabagh1, Омар Саид1, Didier Lebrec2,3, Arieh Bomzon1,4
1Department of Pharmacology, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
2Hémodynamique Splanchnique et de Biologie Vasculaire, INSERM, Hôpital Beaujon, Clichy, France
3Laboratoire dcar
4Division of Gastroenterology, Department of Medicine, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada

Tóm tắt

Abstract: Aims/Background: Vascular hyporesponsiveness to sympathomimetic stimulation occurs in jaundice. Recently, we reported that this vascular adrenergic hyporesponsiveness was associated with the loss of reactivity of vascular α1‐adrenoceptors. This study examines the possibility that the vascular adrenergic hyporesponsiveness is due to down‐regulation of vascular α1‐adrenoceptors. Methods: This question was addressed by measuring the changes in the plasma norepinephrine (NE) and epinephrine (E) concentrations, determined by high performance liquid chromatography, and the affinity and number of α1‐adrenoceptors determined by a competitive antagonist radioligand binding assay in vascular smooth muscle membranes prepared from 3‐day bile duct ligated (BDL) rats. The results were compared to data obtained from 3‐day bile duct manipulated (sham‐operated; SO) and control (C) rats. Results: Compared to C and SO rats, the plasma concentrations of NE and E in the BDL rats were significantly elevated reflecting increased sympathetic nervous system activity. BDL did not change either the affinity or the number of vascular α1‐adrenoceptors. Conclusions: Since the affinity and number of vascular α1‐adrenoceptors were unchanged in the face of elevated plasma concentrations of catecholamines in the BDL rats, we have concluded that down‐regulation of vascular α1‐adrenoceptors does not account for the vascular adrenergic hyporesponsiveness in experimental cholestasis.

Từ khóa


Tài liệu tham khảo

Morandini G, 1966, Contributo allo studio della reattivit vascolare periferica alľangiotensina ed alia noradrenalina in corso di affezioni epatiche, Minerva Med, 57, 2175

10.3109/08860229109022141

Better O S, 1988, The kidney in liver disease, 508

Bomzon A., 1990, Cardiovascular complications of liver disease, 207

Lee S S, 1990, Cardiovascular complications of liver disease, 81

Jacob G, 1993, Cardiac function and responsiveness to β‐adrenoceptor agonists in rats with obstructive jaundice, Am J Physiol, 265, G314

Bomzon A, 1996, The kidney in liver disease, 423

Bomzon A, 1990, Cardiovascular complications of liver disease, 9

10.1042/cs0670177

Bomzon A, 1985, Reversible suppression of the vascular contractile response in rats with obstructive jaundice, J Lab Clin Med, 105, 568

10.1016/0022-4804(87)90140-5

10.1016/0168-8278(90)90274-U

Jacob G, 1993, Peripheral vascular neuroeffector mechanisms in experimental cholestasis, Am J Physiol, 265, G579

10.1016/0006-2952(85)90146-7

10.1016/1056-8719(95)00017-C

10.1042/cs0820147

10.1152/ajpendo.1984.247.1.E13

Gaudin C, 1989, Relations entre les catêcholamines plasmatiques et la sévérité de la maladie de foie et ľhemodynamique des malades atteints de cirrhose, Gastroenterol Clin Biol, 13, 701

10.1007/978-1-4612-4582-7_2

10.1016/S0022-2828(84)80658-6

10.1016/S0021-9258(19)52451-6

10.1038/ki.1974.115

Bravo EL, 1982, Plasma catecholamines in clinical investigation: a useful index or a meaningless number, J Lab Clin Med, 100, 155

10.1042/cs0620247

10.1016/S0168-8278(85)80068-4

10.1002/hep.1840150112

Rector W G, 1994, Prevalence and determinants of elevated plasma norepinephrine concentration in compensated cirrhosis, Am J Gastroenterol, 89, 2049

10.1139/y88-087

10.1016/0024-3205(89)90019-2

10.1152/ajpregu.1991.260.2.R298

10.1002/hep.1840130330

Saito H., 1981, Clinical and experimental studies on the hyperdynamic states in obstructive jaundice, J Jap Surg Soc, 82, 483

Bomzon A, 1985, Cardiovascular function and amine metabolism in liver disease, Rev Clin Basic Pharm, 5, 71

10.1002/hep.1840120306

10.1016/S0008-6363(95)00238-3

10.1111/j.1476-5381.1994.tb14755.x

Rodriguez‐Puyol D, 1988, Plasma catecholamines and urinary excretion of their main metabolites in three models of portal hypertension, Clin Physiol Biochem, 6, 301

10.1002/hep.1840220228

10.1002/hep.1840130413

10.1016/0016-5085(95)90145-0

10.1139/y95-048

10.1076/apab.104.1.30.12864

Ostrow J D., 1993, Hepatic transport and bile secretion: Physiology and Pathophysiology, 673

10.1016/0006-2952(94)00428-O

Thông tin
Thông tin xuất bản

Wiley

Tập 19 Số 3

193-198

Thông tin tác giả