Novel subfamily of adenylyl cyclase 8 in vascular smooth muscle cells: Potential implication in pathological vascular remodelings

The influence of arginine vasopressin (AVP) on agonist-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) accumulation was investigated in vascular smooth muscle cells (VSMC) cultured from rat thoracic aorta. Incubation of VSMC with AVP for 60 s produced a 2- to 2.5-fold enhancement of isoproterenol-induced cAMP formation. AVP also increased cAMP stimulation by the prostaglandin I2 analogue iloprost. The effect of AVP to enhance agonist-stimulated cAMP formation was completely inhibited in cells pretreated with a selective antagonist of V1 vasopressin receptors but was not affected by blockade of V2 receptors. Inhibition of protein kinase C activation failed to alter the action of AVP to potentiate cAMP stimulation, but treatment of cells with calmodulin antagonists significantly attenuated this effect of the peptide. Moreover, depletion of Ca2+ stores with thapsigargin decreased AVP enhancement of isoproterenol-stimulated cAMP by > 70%. The action of AVP to increase cAMP stimulation was also demonstrated in freshly isolated strips of rat aorta where treatment with peptide produced a twofold increase in isoproterenol-stimulated cAMP formation. RNA blot analysis indicated expression in VSMC of mRNA encoding type III adenylyl cyclase, a Ca(2+)-calmodulin-sensitive isoform of the effector. Furthermore, when detergent-solubilized membrane extract was subjected to calmodulin affinity chromatography, a peak of adenylyl cyclase activity was identified which had affinity for calmodulin matrix in the presence of Ca2+. The results indicate that AVP activates V1 receptors in VSMC to enhance agonist-stimulated cAMP formation by a Ca(2+)-calmodulin-dependent mechanism and suggest that type III adenylyl cyclase may provide a focal point in the VSMC for cross talk between constrictor and dilator pathways.

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Adenylyl cyclase isoforms and signal integration in models of vascular smooth muscle cells

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.281.4.h1545 ◽

2001 ◽

Vol 281 (4) ◽

pp. H1545-H1552 ◽

Cited By ~ 22

Author(s):

Jerry G. Webb ◽

Phillip W. Yates ◽

Qing Yang ◽

Yurii V. Mukhin ◽

Stephen M. Lanier

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Adenylyl Cyclase ◽

Cell Line ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Ionophore A23187 ◽

Signal Integration ◽

A7r5 Cells

Adenylyl cyclases present a potential focal point for signal integration in vascular smooth muscle cells (VSMC) influencing contractile state and cellular responses to vessel wall injury. In the present study, we examined the influence of the vasoactive peptide arginine vasopressin (AVP) on cAMP regulation in primary cultures of rat aortic VSMC and in the A7r5 arterial smooth muscle cell line. In cultured VSMC and A7r5 cells, AVP had no effect on basal cAMP but differentially affected β-adrenergic receptor-induced activation of adenylyl cyclase. AVP synergistically increased (twofold) isoproterenol-stimulated cAMP production in VSMC but inhibited the effect of isoproterenol (50%) in the A7r5 cell line. The effects of AVP in both preparations were blocked when cells were pretreated with a selective V1vasopressin receptor antagonist. Moreover, the actions of AVP in both models were dependent on release of intracellular Ca2+ and were mimicked by elevation of Ca2+ with the ionophore A23187 , suggesting that the responses to AVP involve Ca2+-mediated regulation of adenylyl cyclase stimulation. Adenylyl cyclase types I, III, and VIII are stimulated by Ca2+/calmodulin, whereas types V and VI are directly inhibited by Ca2+. RNA blot analysis for effector isotypes indicated that both VSMC and A7r5 cells expressed types III, V, and VI. VSMC also expressed mRNA for type IV and VIII effectors, which could account for the cell-specific responses to peptide hormone and Ca2+.

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Atrial Natriuretic Peptide-C Receptor-Induced Attenuation of Adenylyl Cyclase Signaling Activates Phosphatidylinositol Turnover in A10 Vascular Smooth Muscle Cells

Molecular Pharmacology ◽

10.1124/mol.65.4.917 ◽

2004 ◽

Vol 65 (4) ◽

pp. 917-924 ◽

Cited By ~ 22

Author(s):

Rima Mouawad ◽

Yuan Li ◽

Madhu B. Anand-Srivastava

Keyword(s):

Smooth Muscle ◽

Atrial Natriuretic Peptide ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Adenylyl Cyclase ◽

Natriuretic Peptide ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Phosphatidylinositol Turnover ◽

Atrial Natriuretic

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Localization of Adenylyl Cyclase Isoforms and G Protein-Coupled Receptors in Vascular Smooth Muscle Cells: Expression in Caveolin-Rich and Noncaveolin Domains

Molecular Pharmacology ◽

10.1124/mol.62.5.983 ◽

2002 ◽

Vol 62 (5) ◽

pp. 983-992 ◽

Cited By ~ 103

Author(s):

Rennolds S. Ostrom ◽

Xiaoqiu Liu ◽

Brian P. Head ◽

Caroline Gregorian ◽

Tammy M. Seasholtz ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Adenylyl Cyclase ◽

G Protein ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

G Protein Coupled Receptors ◽

G Protein Coupled

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Peroxynitrite inhibits the expression of Giα protein and adenylyl cyclase signaling in vascular smooth muscle cells

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00841.2007 ◽

2008 ◽

Vol 294 (2) ◽

pp. H775-H784 ◽

Cited By ~ 13

Author(s):

Marcel Bassil ◽

Yuan Li ◽

Madhu B. Anand-Srivastava

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Map Kinase ◽

Adenylyl Cyclase ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

P38 Map Kinase ◽

Nitric Oxide Donor ◽

Dependent Manner

We previously showed that S-nitroso- N-acetylpenicillamine, a nitric oxide donor, decreased the levels and functions of Giα proteins by formation of peroxynitrite (ONOO−) in vascular smooth muscle cells (VSMC). The present studies were undertaken to investigate whether ONOO− can modulate the expression of Giα protein and associated adenylyl cyclase signaling in VSMC. Treatment of A-10 and aortic VSMC with ONOO− for 24 h decreased the expression of Giα-2 and Giα-3, but not Gsα, protein in a concentration-dependent manner; expression was restored toward control levels by 111Mn-tetralis(benzoic acid porphyrin) and uric acid, but not by 1 H[1,2,4]oxadiazole[4,3-a]quinoxaline-1-one (ODQ) and KT-5823. cGMP levels were increased by ∼50% and 150% by 0.1 and 0.5 mM ONOO−, respectively, and attenuated toward control levels by ODQ. In addition, 0.5 mM ONOO− attenuated the inhibition of adenylyl cyclase by ANG II and C-type atrial natriuretic peptide (C-ANP4–23), as well as the inhibition of forskolin-stimulated adenylyl cyclase activity by GTPγS, whereas, the Gs-mediated stimulations were augmented. In addition, 0.5 mM ONOO− decreased phosphorylation of ERK1/2 and p38 MAP kinase and enhanced JNK phosphorylation but did not affect AKT1/3 phosphorylation. These results suggest that ONOO− decreased the expression of Gi proteins and associated functions in VSMC through a cGMP-independent mechanism and may involve the MAP kinase signaling pathway.

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Effects of dexamethasone on G protein levels and adenylyl cyclase activity in rat vascular smooth muscle cells

Journal of Molecular Endocrinology ◽

10.1677/jme.0.0090237 ◽

1992 ◽

Vol 9 (3) ◽

pp. 237-244 ◽

Cited By ~ 11

Author(s):

A. R. McLellan ◽

S. Tawil ◽

F. Lyall ◽

G. Milligan ◽

J. M. C. Connell ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Adenylyl Cyclase ◽

G Proteins ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Cyclase Activity ◽

Adenylyl Cyclase Activity ◽

Catalytic Unit

ABSTRACT Dexamethasone administration in vitro has been shown to increase adenylyl cyclase activity in vascular smooth muscle cells (VSMC) from renal arteries and in non-vascular cell lines. To investigate whether G proteins are involved in this response, cultured VSMC from mesenteric arteries of Sprague—Dawley rats were incubated in the presence and absence of 10 nm dexamethasone for 24 and 48 h. Basal and stimulated adenylyl cyclase activities were increased by approximately 50% after treatment with dexamethasone. The changes were neither specifically associated with ligands which stimulate adenylyl cyclase catalytic unit via Gs (isoproterenol and prostaglandin E1) nor with guanylylimidodiphosphate (0·1 nm), which inhibits the catalytic unit via Gi. This suggests that dexamethasone enhances adenylyl cyclase activity through changes at the level of the catalytic unit, rather than through the G proteins which modulate its activity. No differences were seen in immunoblotting studies of the levels of Giα2, Gsα, Giα3 and β subunits. Similarly, dexamethasone had no effect on the expression of mRNA for Giα2 and Gsα. The results indicate that glucocorticoid-induced increases of adenylyl cyclase activity are due to changes at the level of the adenylyl cyclase catalytic unit rather than alteration of the levels or turnover of Gsα, Giα2, Giα3 and β subunits in the membranes of VSMC.

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