BACKGROUNDThe role played by the nitric oxide (NO) signaling pathway in the aqueous humor dynamics is still unclear. This study was designed to investigate the expression and distribution of NO synthase (NOS) isoforms and guanylate cyclase (GC) in human ciliary body, trabecular meshwork and the Schlemm's canal.

METHODSTwelve eyes after corneal transplantation were used. Expression of three NOS isoforms (i.e. neuronal NOS (nNOS), inducible NOS (iNOS) and endothelial NOS (eNOS)) and GC were assessed in 10 eyes by immunohistochemical staining using monoclonal or polyclonal antibody of NOS and GC. Ciliary bodies were dissected free and the total proteins were extracted. Western blotting was performed to confirm the protein expression of 3 NOS isoforms and GC.

RESULTSExpression of 3 NOS isoforms and GC were observed in the ciliary epithelium, ciliary muscle, trabecular meshwork and the endothelium of the Schlemm's canal. Immunoreactivity of nNOS was detected mainly along the apical cytoplasmic junction of the non-pigmented epithelium (NPE) and pigmented epithelial (PE) cells. Protein expressions of 3 NOS isoforms and GC were confirmed in isolated human ciliary body by Western blotting.

CONCLUSIONSThe expression of NOS isoforms and GC in human ciliary body suggest the possible involvement of NO and cyclic guanosine monophosphate (cyclic GMP, cGMP) signaling pathway in the ciliary body, and may play a role in both processes of aqueous humor formation and drainage.

Ciliary Body ; enzymology ; Guanylate Cyclase ; metabolism ; Humans ; Nitric Oxide Synthase ; metabolism ; Trabecular Meshwork ; enzymology

Animals ; Guanylate Cyclase ; metabolism ; Hypercapnia ; metabolism ; Hypoxia ; metabolism ; Lung ; metabolism ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley ; Receptors, Cytoplasmic and Nuclear ; metabolism ; Soluble Guanylyl Cyclase

OBJECTIVETo determine the CARD11 expression and its prognostic value in diffuse large B cell lymphoma (DLBCL).

METHODSThis retrospective study included previously untreated patients diagnosed with DLBCL from January 2007 to December 2012. Formalin-fixed, paraffin-embedded blocks of these patients were collected. Tissue microarray was built and expression of CARD11 was examined immunohistochemically. Subtype of DLBCL was determined by Hans algorithm (CD10, BCL6, MUM1). The pattern of CARD11 was further studied and their correlation with outcome was analyzed.

RESULTS79 patients with DLBCL were enrolled and two reactive lymph nodes were used as control. The positive rate of high CARD11 expression in DLBCL was 65.33%, which showed no significant associations with patients' characteristics. Positive CARD11 expression was associated with an inferior event free survival (EFS)(2- year EFS: 52.03%vs 86.12%,P=0.036). Even in patients with a high international prognostic index (IPI, 3-5 points), this difference still remained significant (Median EFS not reached vs 557 days,P=0.033).

CONCLUSIONDLBCL patients with high CARD11 expression had a shorter EFS compared with low level of CARD11. This difference remained significant when patients were in high IPI (3-5 points), which might indicate the value of CARD11 in stratification of high-risk DLBCL patients.

CARD Signaling Adaptor Proteins ; genetics ; metabolism ; Disease-Free Survival ; Guanylate Cyclase ; genetics ; metabolism ; Humans ; Lymphoma, Large B-Cell, Diffuse ; diagnosis ; genetics ; metabolism ; Prognosis ; Retrospective Studies

Effects of Ultratiolet (UV) light was studied in isolated thoracic aortae of rabbits and porcine coronary arteries. The following results were obtained. 1) Radiation of UV light did not affect both arterial rings in resting tension. 2) Both arterial preparations contracted with various vasoconstrictors (KCI,NE,PE,BayK 8644 and (+S202 etc.) were relaxed by UV light radiation in a radiation time-dependent fashion. 3) The magnitudes of the relaxation were not significantly different in both the rings with or without intact endothelium. 4) MB and LY markedldy reduced the UV light-induced relaxation in both the rings. 5) PP significantly attenuated the UV light-induced relaxation of rabbit thoracic aorta, but did not affect that of porcine coronary artery. 6) The UV Light-induced relaxation of porcine coronary artery was significantly attenuated by DT or NF, while that of rabbit thoracic aorta was not. 7) (+)S202 significantly potentiated the UV light-induced relaxation of porcine coronary artery contracted with KCI or Hist. Above results suggest that the UV light-induced relaxation of vascular smooth muscles is independent on the endothelium, and the relaxation results from primarily activation of guanylyl cyclase and is in part related to adenylyl cyclase and calcium metabolism. In adddition, a dihydropyridine calcium agonist, (+)S202, may sensitize vascular smooth muscle to the relaxing effect of UV light through some unknown mechanism.
Adenylyl Cyclases ; Aorta, Thoracic ; Calcium* ; Coronary Vessels ; Endothelium ; Guanylate Cyclase ; Metabolism ; Muscle, Smooth* ; Muscle, Smooth, Vascular ; Rabbits ; Relaxation* ; Ultraviolet Rays ; Vasoconstrictor Agents

Pathophysiological implications of the vascular nitric oxide (NO)/cGMP pathway were investigated in various rat models of hypertension. The expression of brain and endothelial constitutive NO synthases (bNOS, ecNOS) was determined by Western blot analysis, and the biochemical activity of soluble and particulate guanylate cyclases (GC) was assessed by the amount of cGMP generated in the thoracic aortae of rats with deoxycorticosterone acetate (DOCA)-salt, two-kidney, one dip (2K1C), and spontaneous hypertension (SHR). Plasma nitrite/ nitrate levels were decreased in DOCA-salt and 2K1C hypertension, and increased in SHR. The vascular expression of bNOS as well as that of ecNOS was decreased along with tissue nitrite/nitrate contents in DOCA-salt and 2K1C hypertension. The expression of both bNOS and ecNOS was increased in SHR with concomitant changes of tissue nitrite/nitrate contents. The activity of soluble GC was decreased, and that of particulate GC was increased in DOCA-salt hypertension. The soluble GC activity was increased, while the particulate GC activity was not affected in 2K1C hypertension. The soluble GC activity was not significantly changed, but the particulate GC activity was decreased in SHR. These results indicate that the high blood pressure is associated with differentially-altered vascular NO/cGMP pathway in different models of hypertension.
Animal ; Aorta, Thoracic/enzymology ; Atrial Natriuretic Factor/blood ; Blotting, Western ; Desoxycorticosterone ; Guanylate Cyclase/metabolism ; Guanylate Cyclase/analysis* ; Hypertension/enzymology* ; Hypertension/chemically induced ; Isoenzymes/metabolism ; Isoenzymes/analysis* ; Male ; Nitrates/blood ; Nitric-Oxide Synthase/metabolism ; Nitrites/blood ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Rats, Sprague-Dawley ; Solubility

The purpose of this study was to investigate the effects of vasonatrin peptide (VNP) on electrically-induced intracellular calcium ([Ca(2+)](i)) transient and mechanism of the effects in the cardiac myocytes. The [Ca(2+)](i) transient was measured with a fluoremetric method. The effects of HS-142-1, 8-Br-cGMP and methylene blue (MB) on [Ca(2+)](i) transient in cardiac myocytes were also determined. Isoproterenol (Iso) at 10(-10)~10(-6) mol/L augmented electrically-induced [Ca(2+)](i) transient dose-dependently, which was (13+/-8)% (P>0.05), (26+/-13)% (P< 0.05), (66+/-10)% (P<0.01), (150+/-10)% (P<0.01) and (300+/-25)% (P<0.01), respectively. These effects were blocked by an beta-adrenergic bloker propranolol (10(-6) mol/L). The effect of Iso (10(-8) mol/L) on [Ca(2+)](i) transient was attenuated in a dose-dependent manner by VNP at 10(-10)~10(-6) mol/L, which was (99+/-3)% (P>0.05), (96+/-2)% (P<0.05), (84+/-6)% (P<0.01), (66+/-3)% (P<0.01) and (62+/-3)% (P<0.01), respectively. 8-Br-cGMP (10(-7)~10(-3) mol/L) aslo attenuated 10(-8) mol/L Iso-induced [Ca(2+)](i) transient dose-dependent. The effect of VNP on [Ca(2+)](i) transient was almost abolished in the presence of HS-142-1 (2x10(-5) mol/L), an antagonist of the natriuretic peptide guanylate cyclase (GC) receptors. MB (10(-5) mol/L), an inhibitor of GC, not only blocked the effect of VNP in myocytes, but also augmented electrically-induced [Ca(2+)](i) transient. VNP and HS-142-1 themselves did not change the [Ca(2+)](i) transient in the cardiac myocytes significantly. But MB augmented the [Ca(2+)](i) transient in the cardiac myocytes significantly. These results suggest that VNP attenuates [Ca(2+)](i) transient induced by Iso. This effect is possibly achieved by binding VNP with the natriuretic peptide GC receptors in the myocytes, leading to an increase in intracellular cGMP.
Animals ; Atrial Natriuretic Factor ; pharmacology ; Calcium ; metabolism ; Calcium Channels ; metabolism ; Cyclic GMP ; metabolism ; Depression, Chemical ; Female ; Guanylate Cyclase ; metabolism ; Isoproterenol ; pharmacology ; Male ; Myocytes, Cardiac ; metabolism ; Rats ; Receptors, Atrial Natriuretic Factor ; metabolism

Reactive oxygen species such as superoxides, hydrogen peroxide (H2O2) and hydroxyl radicals have been suggested to be involved in the catalytic action of nitric oxide synthase (NOS) to produce NO from L-arginine. An examination was conducted on the effects of oxygen radical scavengers and oxygen radical-generating systems on the activity of neuronal NOS and guanylate cyclase (GC) in rat brains and NOS from the activated murine macrophage cell line J774. Catalase and superoxide dismutase (SOD) showed no significant effects on NOS or GC activity. Nitroblue tetrazolium (NBT, known as a superoxide radical scavenger) and peroxidase (POD) inhibited NOS, but their inhibitory actions were removed by increasing the concentration of arginine or NADPH respectively, in the reaction mixture. NOS and NO-dependent GC were inactivated by ascorbate/FeSO4 (a metal-catalyzed oxidation system), 2'2'-azobis-amidinopropane (a peroxy radical producer), and xanthine/xanthine oxidase (a superoxide generating system). The effects of oxygen radicals or antioxidants on the two isoforms of NOS were almost similar. However, H2O2 activated GC in a dose-dependent manner from 100 microM to 1 mM without significant effects on NOS. H2O2-induced GC activation was blocked by catalase. These results suggested that oxygen radicals inhibited NOS and GC, but H2O2 could activate GC directly.
Animal ; Antioxidants/pharmacology ; Brain/enzymology ; Catalase/pharmacology ; Cell Line ; Guanylate Cyclase/metabolism* ; Hydrogen Peroxide/pharmacology ; Macrophages/enzymology ; NADP/pharmacology ; Nitric-Oxide Synthase/metabolism* ; Nitroblue Tetrazolium/pharmacology ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism* ; Signal Transduction ; Superoxide Dismutase/pharmacology

OBJECTIVETo determine the possible difference in vasodialtation effect of quercetin and rutin.

METHODSThe isolated rat thoracic aorta was treated with phenylephrine (PE), and the effects of quercetin and rutin on the preconstricted aorta rings with or without endothelium were determined by organ bath technique. Nitric oxide synthase inhibitor L-N(G)-nitroarginine methyl-ester (L-NAME), guanylyl cyclase inhibitor methylene blue, cyclooxygenase inhibitor indomethacin were used to explore the mechanism.

RESULTSQuercetin (10-160 micromol/L) caused vasorelaxation of aorta rings preconstricted with PE in endothelium-intact and denuded aorta rings in a dose-dependent manner. Rutin(10-160 micromol/L) caused dose-dependent vasorelaxation in endothelium-intact rings preconstricted with phenylephrine, but not in denuded aorta rings. The maximal response (Rmax) values calculated from vasorelaxation curves of quercetin and rutin were (77.20+/-6.11)% and (44.28+/-7.48)%, respectively. There was no difference between median effective concentration (EC(50)) values of quercetin and rutin. Pretreatment with L-NAME (0.1 mmol/L) abolished the vasorelaxation by rutin,but did not influence the vasodilating effect of quercetin in endothelium-intact rings. Pretreatment with methylene blue (10 mmol/L) canceled the vasorelaxation both by quercetin and rutin. Pretreatment with indomethacin (10 micromol/L) attenuated the vasodilatation of quercetin, but did not affect the vascular effect of rutin.

CONCLUSIONThe vasodilatation effect of quercetin is more potent than rutin. The vasodilatation effect of quercetin might be mediated by guanylyl cyclase and cyclooxygenase-dependent pathway, while the vasodilatation by rutin might be via nitric oxide-guanylyl cyclase pathway.

Animals ; Aorta, Thoracic ; drug effects ; Dose-Response Relationship, Drug ; Guanylate Cyclase ; metabolism ; In Vitro Techniques ; Male ; Nitric Oxide ; metabolism ; Phenylephrine ; pharmacology ; Prostaglandin-Endoperoxide Synthases ; metabolism ; Quercetin ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Rutin ; pharmacology ; Vasodilator Agents ; pharmacology

The purpose of this study was to investigate the vasorelaxing effect of vasonatrin peptide (VNP) on human intramammary artery (HIMA).The vasorelaxing effect of VNP on HIMA was measured by means of perfusion in vitro. The effects of HS-142-1, TEA, 8-Br-cGMP and methylene blue (MB) were also observed. It was found that VNP caused a concentration-dependent relaxation in HIMA which was independent of the endothelium. 8-Br-cGMP (0.1-1000 micromol/L) also caused a concentration-dependent relaxation in HIMA. The vasorelaxing effect of VNP disappeared in the presence of HS-142-1 (20 micromol/L), an antagonist of the natriuretic peptide guanylate cyclase (GC) receptor. MB (10 micromol/L), an inhibitor of GC, not only blocked completely the relaxation of HIMA, but also enhanced the vascular contraction induced by norepinephrine. TEA (1 mmol/L), an antagonist of calcium activated potassium channels (K(Ca)), reduced but not completely blocked the vasorelaxing effect of VNP. These findings suggest that VNP can relax HIMA, which is independent of the endothelium. This effect is possibly achieved by the binding of VNP with the natriuretic peptide GC receptors in the smooth muscle cells (SMCs), leading to an increase in intracellular cGMP level. Moreover, the vasorelaxing effect of VNP is associated with K(Ca).
Aged ; Atrial Natriuretic Factor ; pharmacology ; Dose-Response Relationship, Drug ; Humans ; In Vitro Techniques ; Mammary Arteries ; drug effects ; physiology ; Middle Aged ; Potassium Channels, Calcium-Activated ; metabolism ; Receptors, Guanylate Cyclase-Coupled ; metabolism ; Vasodilation ; drug effects ; physiology

Hypoxic pulmonary vasoconstriction (HPV), a unique response of pulmonary circulation, is critical to prevent hypoxemia under local hypoventilation. Hypoxic inhibition of K+ channel is known as an important O2-sensing mechanism in HPV. Carbon monoxide (CO) is suggested as a positive regulator of Ca2+-activated K+ channel (BK(Ca)), a stimulator of guanylate cyclase, and an O2-mimetic agent in heme moiety-dependent O2 sensing mechanisms. Here we compared the effects of CO on the HPV (Po2, 3%) in isolated pulmonary artery (HPV(PA)) and in blood-perfused/ventilated lungs (HPV(lung)) of rats. A pretreatment with CO (3%) abolished the HPV(PA) in a reversible manner. The inhibition of HPV(PA) was completely reversed by 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ), a guanylate cyclase inhibitor. In contrast, the HPV(lung) was only partly decreased by CO. Moreover, the partial inhibition of HPV(lung) by CO was affected neither by the pretreatment with ODQ nor by NO synthase inhibitor (L-NAME). The CO-induced inhibitions of HPV(PA) and HPV(lung) were commonly unaffected by tetraethylammonium (TEA, 2 mM), a blocker of BK(Ca). As a whole, CO inhibits HPV(PA) via activating guanylate cyclase. The inconsistent effects of ODQ on HPV(PA) and HPV(lung) suggest that ODQ may lose its sGC inhibitory action when applied to the blood-containing perfusate.
Animals ; Anoxia/*physiopathology ; Carbon Monoxide/*pharmacology ; Guanylate Cyclase/antagonists & inhibitors/metabolism ; NG-Nitroarginine Methyl Ester/chemistry/pharmacology ; Nitric Oxide Synthase/antagonists & inhibitors/metabolism ; Oxadiazoles/chemistry/pharmacology ; Pulmonary Artery/*physiopathology ; Quinoxalines/chemistry/pharmacology ; Rats ; Tetraethylammonium/chemistry/pharmacology ; Vasoconstriction/*drug effects/physiology