Natriuretic peptide clearance receptor is transcriptionally down-regulated by beta 2-adrenergic stimulation in vascular smooth muscle cells.
Three natriuretic peptide receptors (the ANP-A, ANP-B, and clearance (C) receptors) have been reported. The regulation of these receptors by catecholamines was examined in cultured rat vascular smooth muscle cells. Treatment with norepinephrine decreased the maximum 125I-ANP binding. The competitive binding assay with des[Gln18,Ser19,Gly20,Leu21, Gly22]ANP-(4-23)-NH2 (C-ANF-4-23), a specific ligand for the C receptor, revealed that the decrease in the 125I-ANP binding by norepinephrine was caused by the down-regulation of the C receptor. Isoproterenol also down-regulated the C receptor in a time- and dose-dependent manner. The catecholamine-induced down-regulation of the C receptor was antagonized by a beta 2-selective adrenergic antagonist, ICI 118,551 but not by an alpha 1-, alpha 2-, or beta 1-adrenergic antagonist. Forskolin, NaF and, 8-bromo-cyclic AMP also decreased the C receptor density. The isoproterenol-induced decrease in the C receptor level was further confirmed by affinity cross-linking and Western blot analysis. Northern blot analysis revealed that isoproterenol and 8-bromo-cyclic AMP decreased the steady-state level of C receptor mRNA. By contrast, neither the ANP-A receptor nor the ANP-B receptor mRNA level was affected by 8-bromo-cyclic AMP. The nuclear run-on assay showed that the transcriptional rate of the C receptor gene was decreased by isoproterenol, whereas those of the ANP-A and ANP-B receptor genes were unchanged. Isoproterenol attenuated the clearance of exogenously added ANP and augmented the ANP-stimulated intracellular cyclic GMP production to the same extent as the selective occupancy of the C receptor with C-ANF-(4-23), suggesting that the isoproterenol-induced enhancement of responsiveness to ANP could result not from the sensitization of the ANP-A or ANP-B receptor but from the down-regulation of the C receptor, which leads to the attenuated clearance of ANP. These findings suggest that the beta 2-adrenergic receptor stimulation down-regulates the C receptor through the decrease in the transcriptional rate of the C receptor gene and that the activation of the sympathetic nervous system augments the biological responsiveness to natriuretic peptides by attenuating their metabolic clearance in vascular walls.
Department of Medicine, Kyoto University Faculty of Medicine, Japan.
I
I
Kishimoto
T
T
Yoshimasa
S
S
Suga
Y
Y
Ogawa
Y
Y
Komatsu
O
O
Nakagawa
H
H
Itoh
K
K
Nakao
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001013:Aorta, Thoracic / Q000378:metabolism; D009320:Atrial Natriuretic Factor / Q000378:metabolism* / Q000494:pharmacology; D015152:Blotting, Northern; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D006152:Cyclic GMP / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects*; D006162:Guanylate Cyclase / Q000096:biosynthesis*; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology*; D011412:Propanolamines / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D011869:Radioligand Assay; D051381:Rats; D017208:Rats, Wistar; D018343:Receptors, Adrenergic, beta-2 / Q000187:drug effects / Q000502:physiology*; D017461:Receptors, Atrial Natriuretic Factor / Q000096:biosynthesis*; D012969:Sodium Fluoride / Q000494:pharmacology
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D012333:RNA, Messenger; D018343:Receptors, Adrenergic, beta-2; D005576:Colforsin; D015124:8-Bromo Cyclic Adenosine Monophosphate; C026777:ICI 118551; D009320:Atrial Natriuretic Factor; D012969:Sodium Fluoride; D006162:Guanylate Cyclase; D017461:Receptors, Atrial Natriuretic Factor; C073616:atrial natriuretic factor receptor C; D006152:Cyclic GMP; D007545:Isoproterenol; D009638:Norepinephrine