We hypothesized that aging is characterized by a reduced release of nitric oxide (NO) in response to shear stress in resistance vessels. Mesenteric arterioles and arteries of young (6 mo) and aged (24 mo) male Fischer 344 rats were isolated and cannulated. Shear stress (15 dyn/cm 2 )-induced dilation was significantly reduced and shear stress (1, 5, 10, and 15 dyn/cm 2 )-induced increases in perfusate nitrite were significantly smaller at all shear stress levels in vessels of aged rats. Inhibition of NO synthesis abolished shear stress-induced release of nitrite. Furthermore, shear stress (15 dyn/cm 2 )-induced release of nitrate was significantly higher and total nitrite (nitrite plus nitrate) was significantly lower in vessels of aged rats. Tiron or SOD significantly increased nitrite released from vessels of aged rats, but this was still significantly less than that in young rats. Superoxide production was increased and the activity of SOD was decreased in vessels of aged rats. There were no differences in endothelial NO synthase (eNOS) protein and basal activity or in Cu/Zn-SOD and Mn-SOD proteins in vessels of the two groups, but extracellular SOD was significantly reduced in vessels of aged rats. Maximal release of NO induced by shear stress plus ACh (10 −5 M) was comparable in the two groups, but phospho-eNOS in response to shear stress (15 dyn/cm 2 ) was significantly reduced in vessels of aged rats. These data suggest that an increased production of superoxide, a reduced activity of SOD, and an impaired shear stressinduced activation of eNOS are the causes of the decreased shear stress-induced release of NO in vessels of aged rats. Keywords endothelium; superoxide; superoxide dismutase Age-related endothelial dysfunction has been characterized by reduced agonist-induced vasodilatation (33). In addition, several studies showed that flow-induced dilation, the most physiologically relevant measure of endothelium-dependent regulation of vascular tone, was reduced in healthy elderly humans and aged animals (4,7,25,36) and that the sensitivity of arteriolar endothelium to fluid shear stress is decreased with advancing age (31). The

Background: Surgical closure of patent ductus arteriosus (PDA) with severe pulmonary arterial hypertension in adults carries higher risk than in children. Objectives: To investigate the application of self-expandable occluders for transcatheter closure of PDA associated with severe pulmonary arterial hypertension in adults, and the assessment of immediate and shortterm results. Methods: 29 adult patients (6 men, 23 women) underwent attempted transcatheter closure of PDA at a mean (standard deviation (SD)) age of 31.1 (11.4) years (range 18-58 years) and a mean (SD) weight of 54.1 (7.1) kg (range 42-71 kg). On the basis of haemodynamic and clinical data obtained before and after trial occlusion, the final duct occlusion was determined and carried out. Radiographs of the chest, electrocardiograms and echocardiograms were used for follow-up evaluation of the treatment within 1 day, 1 month and 3-6 months after successful closure. Results: 20 of the 29 patients had successful occlusion (group 1), and 9 patients failed (named group 2). In group 1, in which occlusion was successful, mean (SD) pulmonary arterial pressures decreased markedly after trial occlusion: 78 (19.3) mm Hg (range 50-125 mm Hg) before occlusion and 41 (13.8) mm Hg (range 23-77 mm Hg) after occlusion. Systemic arterial oxygen saturation was found to be .90% in 19 patients and ,90% in the remaining patient before inhalation of oxygen, and .95% during inhalation of oxygen or after occlusion in all 20 patients. In group 2, the occlusion was not successful, because in two patients the device was not available; another two patients showed worsening of symptoms. The other five patients showed increased pulmonary arterial pressures after trial closure; their mean (SD) pulmonary arterial pressures increased by 10.3 (6) mm Hg (4-16 mm Hg) after trial occlusion, and systemic arterial oxygen saturation was 85.5% (2.6%) (range 82.6-88%) before inhalation of oxygen and 94.7% (1.7%) (range 90.7-99.1%) during inhalation of oxygen. In group 1, the dimensions of the left atrium, left ventricle and pulmonary artery increased considerably in 3-6-months of follow-up compared with those of preocclusion. Conclusions: Transcatheter closure is an effective treatment for adults with PDA associated with reversible severe pulmonary arterial hypertension. Further research is needed for the evaluation of long-term results.

Background-Cardiovascular magnetic resonance has provided important information on the diagnosis and risk stratification of hypertrophic cardiomyopathy (HCM) in adults; however, comparable data are absent for HCM in children.

Genotype-phenotype correlation of hypertrophic cardiomyopathy (HCM) has been challenging because of the genetic and clinical heterogeneity. To determine the mutation profile of Chinese patients with HCM and to correlate genotypes with phenotypes, we performed a systematic mutation screening of the eight most commonly mutated genes encoding sarcomere proteins in 200 unrelated Chinese adult patients using direct DNA sequencing. A total of 98 mutations were identified in 102 mutation carriers. The frequency of mutations in MYH7, MYBPC3, TNNT2 and TNNI3 was 26.0, 18.0, 4.0 and 3.5 % respectively. Among the 200 genotyped HCM patients, 83 harbored a single mutation, and 19 (9.5 %) harbored multiple mutations. The number of mutations was positively correlated with the maximum wall thickness. We found that neither particular gene nor specific mutation was correlated to clinical phenotype. In summary, the frequency of multiple mutations was greater in Chinese HCM patients than in the Caucasian population. Multiple mutations in sarcomere protein may be a risk factor for left ventricular wall thickness.

The purpose of this study was to investigate the mechanisms that regulate superoxide (O(2)(*-)) production as a function of an acute elevation of intravascular pressure and age. Mesenteric arteries isolated from young (6 mo) and aged (24 mo) male Fischer 344 rats were used. O(2)(*-) production in vessels in response to 80 (normal pressure, NP) and 180 (high pressure, HP) mmHg was determined by the superoxide dismutase-inhibitable nitroblue tetrazolium (NBT) reduction assay. In vessels exposed to NP, O(2)(*-) production was significantly higher in aged than in young vessels (32.7 +/- 7.0 vs. 15.4 +/- 2.4 nmol.mg(-1).30 min(-1)). HP enhanced O(2)(*-) production in vessels of both groups, but the enhancement was significantly greater in aged than in young vessels (63.4 +/- 6.7 vs. 32.7 +/- 4.3 nmol.mg(-1).30 min(-1)). Apocynin (100 micromol/l) attenuated HP-induced increases in O(2)(*-) production in both groups, whereas allopurinol (100 micromol/l) and N(omega)-nitro-L-arginine methyl ester (100 mumol/l) inhibited the response only in aged vessels. Confocal microscopy showed increases in O(2)(*-) in response to HP in endothelial and smooth muscle layers of both groups, with much greater fluorescent staining in aged than in young rats and in the endothelium than in smooth muscle cells. No significant changes in NAD(P)H oxidase gene and protein expressions were observed in vessels of the two groups. Upregulation of protein expression of xanthine oxidase was detected in aged vessels. We conclude that NAD(P)H oxidase contributes importantly to HP-induced enhanced O(2)(*-) production in vessels of both young and aged rats, whereas xanthine oxidase and nitric oxide synthase-dependent O(2)(*-) production also contribute to the enhancement in mesenteric arteries of aged rats.

Our data provide new evidence for the contribution of spinal Sirt1 to the initiation and maintenance of neuropathic pain. The antinociceptive effects of resveratrol may be mediated through the activation of spinal Sirt1 in CCI rats.

Women with functional ovaries have a lower cardiovascular risk than men and postmenopausal women. However, oestrogen replacement therapy remains controversial. This study examined the effect of ovarian hormone deficiency and oestrogen replacement on ventricular myocyte contractile function and expression of β-adrenoceptors (β-ARs). Female Sprague-Dawley rats were subjected to bilateral ovariectomy (OVX) or sham operation (Sham). A subgroup of OVX rats received oestrogen (E 2 ) replacement (40 μg kg −1 day −1 ) for 4 weeks. Cardiomyocyte shortening was evaluated in basal conditions and in the presence of isoprenaline (ISO). The expression of β-ARs was assessed by Western blotting. The presence of lactate dehydrogenase (LDH) activity in the coronary effluent was determined. Ovariectomy promoted body weight gain associated with reduced serum E 2 and uterine weight, all of which were abolished by treatment with E 2 . Ovariectomy increased the amplitude of both basal and ISO-stimulated contractions, increased LDH release, upregulated β 1 -AR expression and downregulated β 2 -AR expression, all of which were restored by treatment with E 2 . A β 1 -AR antagonist, CGP20712A, but not a β 2 -AR antagonist, ICI118,551, significantly decreased the amplitude of ventricular myocyte shortening. Oestrogen decreased cardiomyocyte contraction and the expression of β 1 -AR, and increased expression of β 2 -AR, and all these effects were abolished by the E 2 receptor antagonist, ICI182,780. These data suggest that oestrogen plays a cardioprotective role in female rat hearts subjected to ischaemia-reperfusion injury, and the effects of oestrogen are associated with decreased cardiomyocyte contraction and expression of β 1 -AR, and increased expression of β 2 -AR.

G protein-coupled receptor (GPR) 30 is a novel estrogen receptor. Recent studies suggest that activation of the GPR30 confers rapid cardioprotection in isolated rat heart. It is unknown whether chronic activation of GPR30 is beneficial or not for heart failure. In this study we investigated the cardiac effect of sustained activation or inhibition of GPR30. Female Sprague–Dawley rats were divided into 7 groups #2Q1: sham surgery (Sham), bilateral ovariectomy (OVX), OVX+estrogen (E2), OVX+isoproterenol (ISO), OVX+ISO+G-1, OVX+ISO+E2+G15, OVX+ISO+E2. ISO (85 mg/kg×17 day, sc) was given to make the heart failure models. G-1(120 µg/kg·d×14 day) was used to activate GPR30 and G15 (190 µg/kg·d×14 day) was used to inhibit GPR30. Concentration of brain natriuretic peptide in serum, masson staining in isolated heart, contractile function and the expression of β1 and β2- adrenergic receptor (AR) of ventricular myocytes were also determined. Our data showed that ISO treatment led to heart failure in OVX rats. G-1 or E2 treatment decreased concentration of brain natriuretic peptide, reduced cardiac fibrosis, and enhanced contraction of the heart. Combined treatment with β1 (CGP20712A) and β2-AR (ICI118551) antagonist abolished the improvement of myocardial function induced by G-1. We also found that chronic treatment with G-1 normalized the expression of β1-AR and increased the expression of β2-AR. Our results indicate that chronic activation of the GPR30 with its agonist G-1 attenuates heart failure by normalizing the expression of β1-AR and increasing the expression of β2-AR.