TNF-alpha and IFN-gamma induce expression of nitric oxide synthase in cultured rat medullary interstitial cells

Cytokines increase the expression of the inducible (type II) nitric oxide synthase (NOS) in macrophages, liver, and renal epithelial cells. Previously, we found that cultured rat medullary interstitial cells (RMIC) contain high levels of soluble guanylyl cyclase. To determine whether these cells can also produce NO, we studied the effects of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) on NO production, NOS II mRNA, and NOS II protein expression. Both TNF-alpha and IFN-gamma, in the presence of a low concentration of the other cytokine, caused dose-dependent increases in NO production. Exposure to TNF-alpha and IFN-gamma stimulated the production of NOS II mRNA, as determined by Northern blotting. Restriction mapping of reverse transcription-polymerase chain reaction products indicated that normal cells contained macrophage NOS II, whereas cytokine-stimulated cells contained primarily vascular smooth muscle NOS II and some macrophage NOS II. The appearance of NOS II protein was demonstrated by Western blotting. RMIC cell guanosine 3',5'-cyclic monophosphate accumulation increased 129-fold in response to the cytokines. NOS inhibitors decreased nitrite production. We conclude that 1) TNF-alpha and IFN-gamma induce the expression of vascular smooth muscle NOS II and production of NO in RMIC, and 2) NO acts as an autocrine activator of the soluble guanylyl cyclase in RMIC.

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Role of Aging Versus the Loss of Estrogens in the Reduction in Vascular Function in Female Rats

Endocrinology ◽

10.1210/en.2008-0640 ◽

2008 ◽

Vol 150 (1) ◽

pp. 212-219 ◽

Cited By ~ 27

Author(s):

James P. Stice ◽

Jason P. Eiserich ◽

A. A. Knowlton

Keyword(s):

Nitric Oxide ◽

Smooth Muscle ◽

Nitric Oxide Synthase ◽

Vascular Smooth Muscle ◽

Guanylyl Cyclase ◽

Vascular Function ◽

Soluble Guanylyl Cyclase ◽

Female Rats ◽

Oxide Synthase

Although aging is known to lead to increased vascular stiffness, the role of estrogens in the prevention of age-related changes in the vasculature remains to be elucidated. To address this, we measured vascular function in the thoracic aorta in adult and old ovariectomized (ovx) rats with and without immediate 17β-estradiol (E2) replacement. In addition, aortic mRNA and protein were analyzed for proteins known to be involved in vasorelaxation. Aging in combination with the loss of estrogens led to decreased vasorelaxation in response to acetylcholine and sodium nitroprusside, indicating either smooth muscle dysfunction and/or increased fibrosis. Loss of estrogens led to increased vascular tension in response to phenylephrine, which could be partially restored by E2 replacement. Levels of endothelial nitric oxide synthase and inducible nitric oxide synthase did not differ among the groups, nor did total nitrite plus nitrate levels. Old ovx exhibited decreased expression of both the α and β-subunits of soluble guanylyl cyclase (sGC) and had impaired nitric oxide signaling in the vascular smooth muscle. Immediate E2 replacement in the aged ovx prevented both the impairment in vasorelaxation, and the decreased sGC receptor expression and abnormal sGC signaling within the vascular smooth muscle. The combination of loss of estradiol and aging leads to increased constriction (phenylephrine) and decreased relaxation with nitric oxide. Reduced soluble guanylyl cyclase mediates these changes.

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The role of nitric oxide synthase/nitric oxide in vascular smooth muscle control

Perfusion ◽

10.1177/026765910001500203 ◽

2000 ◽

Vol 15 (2) ◽

pp. 97-104 ◽

Cited By ~ 31

Author(s):

D Bradford Sanders ◽

Tara Kelley ◽

Douglas Larson

Keyword(s):

Nitric Oxide ◽

Smooth Muscle ◽

Nitric Oxide Synthase ◽

Vascular Smooth Muscle ◽

Vascular Function ◽

No Production ◽

Amyl Nitrite ◽

Vascular Compliance ◽

Oxide Synthase

Vascular compliance is dependent on endogenous and exogenous sources of nitric oxide (NO). In a discussion of therapeutics and NO derived via nitric oxide synthase (NOS) enzymes, it is necessary to examine the pathways of each drug to provide the clinical perfusionist with a greater understanding of the role of NOS/NO in vascular function. Endothelial-derived NO is a contributor in the vasoregulation of vascular smooth muscle. Therapeutics seek to mimic the vasodilatory effects of the endogenous NO. The therapeutics included in this review are nitroglycerin, nitroprusside, amyl nitrite, and inhalation of NO. L-Arginine supplementation provides additional substrate for the endogenous pathway that can augment NO production. NO is a small bioactive molecule involved in various biochemical pathways. Dysregulation of NO production can impair normal physiologic control of vascular compliance. Therefore, the purpose of this review is to provide the perfusionist with an understanding of the biochemical and pharmacological aspects of NOS/NO associated with vascular function.

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Halothane and Isoflurane Inhibit Endothelium-derived Relaxing Factor-dependent Cyclic Guanosine Monophosphate Accumulation in Endothelial Cell-Vascular Smooth Muscle Co-cultures Independent of an Effect on Guanylyl Cyclase Activation

Anesthesiology ◽

10.1097/00000542-199510000-00023 ◽

1995 ◽

Vol 83 (4) ◽

pp. 823-834. ◽

Cited By ~ 29

Author(s):

Roger A. Johns ◽

Alexandra Tichotsky ◽

Michael Muro ◽

James P. Spaeth ◽

Timothy D. Le Cras ◽

...

Keyword(s):

Nitric Oxide ◽

Smooth Muscle ◽

Endothelial Cell ◽

Nitric Oxide Synthase ◽

Vascular Smooth Muscle ◽

Cyclic Gmp ◽

Guanylyl Cyclase ◽

Calcium Ionophore ◽

Inhalational Anesthetics ◽

Oxide Synthase

Background Interaction of inhalational anesthetics with the nitric oxide signaling pathway and the mechanism of such effects are controversial. The aim of this study was to clarify the sites and mechanism of inhalational anesthetic interaction with the vascular nitric oxide and guanylyl cyclase signaling pathway. Methods To specifically study the mechanism of anesthetic interaction with the nitric oxide-guanylyl cyclase pathway, cultured vascular smooth muscle and endothelial cell-vascular smooth muscle (EC-VSM) co-culture models were chosen. Monolayer cultures of VSM with or without cultured endothelial cells grown on microcarrier beads were preequilibrated with anesthetic and stimulated with agonists. The effect of inhalational anesthetics on cyclic guanosine monophosphate (GMP) content of unstimulated VSM and of VSM in which soluble guanylyl cyclase had been activated by the endothelium-independent nitrovasodilators, sodium nitroprusside, nitroglycerin, or nitric oxide was determined. Experiments were also performed to assess the effect of inhalational anesthetics on unstimulated endothelial cell-vascular smooth muscle co-cultures and on co-cultures in which nitric oxide synthase and subsequent cyclic GMP production had been activated by the receptor-mediated agonists bradykinin and adenosine triphosphate and by the non-receptor-mediated calcium ionophore A23187. Results Increasing concentrations of halothane and isoflurane from 0.5 to 5% had no effect on basal cyclic GMP concentrations in cultured VSM alone or in endothelial cell-vascular smooth muscle co-cultures, and had no effect on sodium nitroprusside, nitroglycerin, or nitric oxide stimulated cyclic GMP accumulation in cultured VSM. In agonist-stimulated co-cultures, however, halothane and isoflurane significantly (P < 0.05) inhibited increases in cyclic GMP concentration in response to both receptor- and non-receptor-mediated nitric oxide synthase activating agents. Conclusions Inhalational anesthetics do not stimulate or inhibit basal cyclic GMP production in co-cultures or VSM, suggesting that inhalational anesthetics do not activate soluble or particulate guanylyl cyclase and do not activate nitric oxide synthase. Inhalational anesthetics do not inhibit nitrovasodilator-induced cyclic GMP formation, suggesting a lack of interference with soluble guanylyl cyclase activation. Inhalational anesthetics inhibit both agonist and calcium ionophore-stimulated nitric oxide-dependent cyclic GMP accumulation in endothelial cell-vascular smooth muscle co-cultures. Consistent with previous vascular ring studies, anesthetics appear to inhibit nitric oxide-guanylyl cyclase signaling distal to receptor activation in the endothelial cell and proximal to nitric oxide activation of guanylyl cyclase.

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