Isoproterenol and cAMP regulation of the human brain natriuretic peptide gene involves Src and Rac

• Published in: American journal of physiology: endocrinology and metabolism Vol. 278; no. 6; pp. E1115 - E1123
• Main Authors: He, Quan, Wu, Guiyun, Lapointe, Margot C
• Format: Journal Article
• Language: English
• Published: United States 01.06.2000
• Subjects: Adrenergic beta-Agonists - pharmacology; Adrenergic beta-Antagonists - pharmacology; Animals; Animals, Newborn; Cyclic AMP - pharmacology; Cyclic AMP-Dependent Protein Kinases - antagonists & inhibitors; Cyclic AMP-Dependent Protein Kinases - metabolism; Enzyme Inhibitors - pharmacology; Gene Expression Regulation - drug effects; Gene Transfer Techniques; GTP-Binding Protein alpha Subunits, Gi-Go - antagonists & inhibitors; GTP-Binding Protein alpha Subunits, Gi-Go - physiology; Humans; Isoproterenol - pharmacology; Luciferases - genetics; Myocardium - metabolism; Natriuretic Peptide, Brain - genetics; Promoter Regions, Genetic; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, beta - physiology
• ISSN: 0193-1849; 1522-1555
• DOI: 10.1152/ajpendo.2000.278.6.e1115

Hypertension and Vascular Research Division, Henry Ford Hospital, Detroit, Michigan 48202 Brain natriuretic peptide (BNP) gene expression and chronic activation of the sympathetic nervous system are characteristics of the development of heart failure. We studied the role of the -adrenergic signaling pathway in regulation of the human BNP (hBNP) promoter. An hBNP promoter ( 1818 to +100) coupled to a luciferase reporter gene was transferred into neonatal cardiac myocytes, and luciferase activity was measured as an index of promoter activity. Isoproterenol (ISO), forskolin, and cAMP stimulated the promoter, and the 2 -antagonist ICI 118,551 abrogated the effect of ISO. In contrast, the protein kinase A (PKA) inhibitor H-89 failed to block the action of cAMP and ISO. Pertussis toxin (PT), which inactivates G i , inhibited ISO- and cAMP-stimulated hBNP promoter activity. The Src tyrosine kinase inhibitor PP1 and a dominant-negative mutant of the small G protein Rac also abolished the effect of ISO and cAMP. Finally, we studied the involvement of M-CAT-like binding sites in basal and inducible regulation of the hBNP promoter. Mutation of these elements decreased basal and cAMP-induced activity. These data suggest that -adrenergic regulation of hBNP is PKA independent, involves a G i -activated pathway, and targets regulatory elements in the proximal BNP promoter. cardiomyocytes; gene regulation; adrenergic signaling; M-CAT elements; protein kinase A