|
|
|
|
SB Liggett
Department of Medicine (Pulmonary), Duke University Medical Center, Durham, North Carolina 27710.
beta 3-Adrenergic receptors (beta 3AR) mediate lipolytic and thermogenic responses in rodent adipose tissues in vitro, and "atypical" beta AR agonists that active these receptors have potent therapeutic effects in in vivo rodent models of adult-onset diabetes and obesity. However, experiments with rodent cells that natively express the beta 3AR, as well as those with cells that express cloned rodent beta 3AR, have suggested that the pharmacological properties of the rodent and human beta 3AR differ. Given that rodent models of obesity and diabetes are used to develop human therapeutic agents, we sought to compare directly the ligand-binding and functional properties of the rat and human beta 3AR in parallel studies using Chinese hamster ovary cells expressing the recombinant receptors. The endogenous catecholamines epinephrine (EPI) and norepinephrine (NE) were found to have low affinities (micromolar) for the beta 3AR of both species. The rank orders of potency of various agonists in stimulating adenylyl cyclase were clearly different, i.e., for the human beta 3AR, CGP12177 (CGP) > isoproterenol (ISO) > or = BRL34377 (BRL) = Pindolol > NE > EPI; for the rat, CGP > or = BRL > ISO > or = NE > Pindolol > EPI. The intrinsic activities of various agonists were also different, with the following rank orders (compared with ISO): for the human beta 3AR, NE > EPI > BRL = CGP > Pindolol; for the rat beta 3AR, BRL > NE > EPI > CGP > Pindolol. Competition binding studies with 125I-cyanopindolol and these agonists gave similar rank orders of potency. Thus, although the human and rat receptors exhibited similar properties with respect to catecholamine agonists, numerous differences in the potency and efficacy of synthetic noncatecholamine agonists were noted, indicating that the action of atypical agonists at rodent beta 3AR may not be predictive of therapeutic potential in humans.
This article has been cited by other articles:
![]() |
T. Takasu, M. Ukai, S. Sato, T. Matsui, I. Nagase, T. Maruyama, M. Sasamata, K. Miyata, H. Uchida, and O. Yamaguchi Effect of (R)-2-(2-Aminothiazol-4-yl)-4'-{2-[(2-hydroxy-2-phenylethyl)amino]ethyl} Acetanilide (YM178), a Novel Selective beta3-Adrenoceptor Agonist, on Bladder Function J. Pharmacol. Exp. Ther., May 1, 2007; 321(2): 642 - 647. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. W. D. Jurgens, K. E. Rau, C. A. Knudson, J. D. King, P. A. Carr, J. E. Porter, and V. A. Doze {beta}1 Adrenergic Receptor-Mediated Enhancement of Hippocampal CA3 Network Activity J. Pharmacol. Exp. Ther., August 1, 2005; 314(2): 552 - 560. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. L. H. Schiffelers, W. H. M. Saris, F. Boomsma, and M. A. van Baak {beta}1- and {beta}2-Adrenoceptor-Mediated Thermogenesis and Lipid Utilization in Obese and Lean Men J. Clin. Endocrinol. Metab., May 1, 2001; 86(5): 2191 - 2199. [Abstract] [Full Text] |
||||
![]() |
A. A. Konkar, S. S. Vansal, G. Shams, P. F. Fraundorfer, W.-P. Zheng, V. I. Nikulin, J. D. L. Angeles, R. H. Fertel, D. D. Miller, and D. R. Feller beta -Adrenoceptor Subtype Activities of Trimetoquinol Derivatives: Biochemical Studies on Human beta -Adrenoceptors Expressed in Chinese Hamster Ovary Cells J. Pharmacol. Exp. Ther., November 1, 1999; 291(2): 875 - 883. [Abstract] [Full Text] |
||||
![]() |
S. L. H. Schiffelers, V. J. A. van Harmelen, H. A. J. de Grauw, W. H. M. Saris, and M. A. van Baak Dobutamine as selective beta 1-adrenoceptor agonist in in vivo studies on human thermogenesis and lipid utilization J Appl Physiol, September 1, 1999; 87(3): 977 - 981. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. V. Sennitt, A. J. Kaumann, P. Molenaar, L. J. Beeley, P. W. Young, J. Kelly, H. Chapman, S. M. Henson, J. M. Berge, D. K. Dean, et al. The Contribution of Classical (beta 1/2-) and Atypical beta -Adrenoceptors to the Stimulation of Human White Adipocyte Lipolysis and Right Atrial Appendage Contraction by Novel beta 3-Adrenoceptor Agonists of Differing Selectivities J. Pharmacol. Exp. Ther., June 1, 1998; 285(3): 1084 - 1095. [Abstract] [Full Text] |
||||
![]() |
D. S. Meyers, S. Skwish, K. E. J. Dickinson, B. Kienzle, and C. M. Arbeeny {beta}3-Adrenergic Receptor-Mediated Lipolysis and Oxygen Consumption in Brown Adipocytes from Cynomolgus Monkeys J. Clin. Endocrinol. Metab., February 1, 1997; 82(2): 395 - 401. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Jockers, A. D. Silva, A. D. Strosberg, M. Bouvier, and S. Marullo New Molecular and Structural Determinants Involved in beta(2)-Adrenergic Receptor Desensitization and Sequestration J. Biol. Chem., April 19, 1996; 271(16): 9355 - 9362. [Abstract] [Full Text] [PDF] |
||||