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.
Kishimoto
I
I
Department of Medicine, Kyoto University Faculty of Medicine, Japan.
Yoshimasa
T
T
Suga
S
S
Ogawa
Y
Y
Komatsu
Y
Y
Nakagawa
O
O
Itoh
H
H
Nakao
K
K
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