TY - JOUR
T1 - Caveolae-independent activation of protein kinase A in rat neonatal myocytes
AU - Fukutomi, Masashi
AU - Nishida, Motohiro
AU - Maruyama, Yoshiko
AU - Kobayashi, Hiroyuki
AU - Kurose, Hitoshi
PY - 2005/6
Y1 - 2005/6
N2 - Cardiomyocytes express both β1- and β2- adrenergic receptors, and these receptors play a differential role in chronotropic and inotropic effects of the heart. Caveolae are known as an important regulator of G-protein-coupled receptor signaling. In the present report, we examined whether caveolae have a role in β-adrenergic receptor-stimulated cAMP production and protein kinase A activation in neonatal myocytes. Isoproterenol-stimulated cAMP production was mediated by β1- and β2-subtypes, which depends on the receptor number of each subtype. However, protein kinase A activation was exclusively mediated by the β1-subtype. Disruption of caveolae by methyl-β-cyclodextrin treatment did not affect the relative contribution of subtypes to isoproterenol-stimulated cAMP production, β1- Subtype-mediated protein kinase A activation was also not affected by the disruption of caveolae. These results suggest that β1-adrenergic receptor-mediated protein kinase A activation is compartmentalized and independent of caveolae.
AB - Cardiomyocytes express both β1- and β2- adrenergic receptors, and these receptors play a differential role in chronotropic and inotropic effects of the heart. Caveolae are known as an important regulator of G-protein-coupled receptor signaling. In the present report, we examined whether caveolae have a role in β-adrenergic receptor-stimulated cAMP production and protein kinase A activation in neonatal myocytes. Isoproterenol-stimulated cAMP production was mediated by β1- and β2-subtypes, which depends on the receptor number of each subtype. However, protein kinase A activation was exclusively mediated by the β1-subtype. Disruption of caveolae by methyl-β-cyclodextrin treatment did not affect the relative contribution of subtypes to isoproterenol-stimulated cAMP production, β1- Subtype-mediated protein kinase A activation was also not affected by the disruption of caveolae. These results suggest that β1-adrenergic receptor-mediated protein kinase A activation is compartmentalized and independent of caveolae.
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U2 - 10.1254/jphs.FP0050244
DO - 10.1254/jphs.FP0050244
M3 - Article
C2 - 15942126
AN - SCOPUS:21744443767
VL - 98
SP - 168
EP - 174
JO - Journal of Pharmacological Sciences
JF - Journal of Pharmacological Sciences
SN - 1347-8613
IS - 2
ER -