Catecholamines stimulate interleukin-6 synthesis in rat cardiac fibroblasts.
Proinflammatory cytokines have been implicated in the pathophysiology of different heart diseases. Recent evidence suggests that interleukin-6 (IL--6) may play a role in mechanisms leading to cardiac hypertrophy. In addition, catecholamines are known to induce cardiac hypertrophy. In the present study, we examined whether cardiac fibroblasts may be a potential source of IL--6 production in the rat heart and whether catecholamines can modulate the IL--6 synthesis. Only a small amount of IL--6 mRNA was detected in unstimulated rat cardiac fibroblasts. However, a 50-fold increase of IL--6 mRNA was found after stimulation with norepinephrine (NE). Addition of carvedilol, a alpha- and beta-adrenergic receptor antagonist, prevented almost completely the NE-induced synthesis of IL--6 mRNA. Phenylephrine, an alpha-adrenergic agonist, and isoproterenol, a beta-adrenergic agonist, also induced an increase in IL--6. However, the stimulation via beta-receptors led to a more pronounced elevation. These data show that NE increases IL--6 expression in rat cardiac fibroblasts and that IL--6 may play an important autocrine/paracrine role in cardiac disease states associated with hypertrophy.
Bürger
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Carl-Ludwig-Institut für Physiologie, Universität Leipzig, D-04103 Leipzig, Germany.
Benicke
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Deten
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Zimmer
H G
HG
D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics; D005260:Female; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism* / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000235:genetics; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011942:Receptors, Adrenergic, alpha / Q000502:physiology; D011943:Receptors, Adrenergic, beta / Q000502:physiology
D016207:Cytokines; D015850:Interleukin-6; D012333:RNA, Messenger; D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D009638:Norepinephrine