Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of human myocardial enzymes in sudden coronary death (SCD) was quantitatively histochemically examined. The activity of succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), beta-oxybutyrate dehydrogenase (beta-OBDH), alpha-glycerolphosphate dehydrogenase (alpha-GPDH), NAD-diaphorase (NAD-ase), and glucose-6-phosphate dehydrogenase (G-6-PDH) was measured on prompt autopsies (up to 3 hours of death onset). beta-OBDH and LDH showed an increase in activity in the myocardium from the subjects who had suddenly died from coronary heart disease without evident changes in the heart. In SCD in the presence of small cardiosclerosis, the activity of the enzymes characterizing the major processes of energy generation was also enhanced, which was caused by moderately severe myocardial hypertrophy. In the myocardium from the subjects who had died from coronary heart disease in the presence of large postinfarction cardiosclerosis, the activity of the enzymes was directly related to the degree of myocardial hypertrophy and the signs of chronic heart failure. As myocardial hypertrophy progressed, the enzymatic activity rose, but there were signs of chronic heart failure, it fell. The findings suggest that the changes in myocardial enzymatic activity in SCD are heterogeneous and associated with the type of prior abnormalities in the cardiovascular system.
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PMID:[Disorders of myocardial metabolism in sudden coronary death in the presence of coronary atherosclerosis: findings of quantitative histoenzymologic studies]. 221 37

Enzymes in the human myocardium following sudden death were examined for activity in a quantitative histoenzymological study, these were NAD-dependent dehadrogenases of succinate (SDG), lactate (LDG), beta-hydroxybutyrate (beta-HOBDG), alpha-glycerophosphate (alpha-GPDG), alcohol (ADG), glucoso-6-phosphate (G-6-PDG), and NAD-diaphorase (NADse), and catalase. Autopsies were performed within 3 h after death. beta-HOBDG and LDG were found to show an increase in activity in the cardiomyocytes of sudden death subjects with coronary heart disease without apparent changes. In the myocardium from death subjects with coronary heart disease and large postinfarct cardiosclerosis, the activity of the enzymes was directly related to the severity of myocardial hypertrophy and signs of chronic heart failure. As myocardial hypertrophy developed, the enzyme activity increased; when there appeared signs of chronic heart failure it decreased. The myocardium from sudden death subjects with alcoholic cardiomyopathy showed diminished redox enzyme activity and higher activity of the enzyme utilizing alcohol (ADG and catalase). The findings suggest that changes in the enzyme activity in the myocardium are of various type and depend on previous cardiac abnormalities.
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PMID:Quantitative histoenzymological characteristics of the myocardium in sudden cardiac death. 252 98

Quantitative histochemical assays of several enzymes (succinic, lactic, beta-hydroxybutyrate, alpha-glycerophosphate, and glucose-6-phosphate dehydrogenases, NAD diaphorase, and phosphorylase) in the myocardium of persons who had died suddenly with postinfarctional cardiosclerosis have failed to reveal any changes specific for this patient group. Direct correlations were established between the enzyme activities assayed, on the one hand, and the extent of myocardial hypertrophy and the signs of chronic heart failure, on the other. The activities of beta-hydroxybutyrate dehydrogenase and glucose-6-phosphate dehydrogenase, which are involved in fatty acid utilization and in the pentose phosphate pathway, were elevated in cases of moderate hypertrophy, as were those of all redox enzymes in cases of strongly marked hypertrophy, although they were reduced in cases with signs of chronic cardiac failure despite the presence of considerable myocardial hypertrophy. Areas of acute myocardial ischemia were discovered in 45% of the cases.
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PMID:[Histochemical study of the enzyme activity of the myocardium of sudden death victims with postinfarct cardiosclerosis]. 296 Feb 98

Recently, we have demonstrated a decreased neuronal isoform of nitric oxide synthase (nNOS) message in the hypothalamus of rats with heart failure (HF). The purpose of this study was to determine the changes in NADPH-diaphorase (a commonly used marker for neuronal NOS activity) positive neurons in specific hypothalamic sites of rats with HF. After a standard histochemical protocol, NOS positive neurons were measured in paraventricular nucleus (PVN), supraoptic nucleus (SON), median preoptic area (MePO), subfornical organ (SFO), organum vasculosum of the lamina terminalis (OVLT) and lateral hypothalamus (LH) of rats with coronary artery ligation (HF group; n=8) and sham-operated control rats (n=9). A total of 4 months after coronary ligation, the rats in the HF group displayed infarcts greater than at least 35% of the left ventricular wall (n = 8). Sham-operated rats had no observable damage to the myocardium. Rats with HF had a significantly lower number of NOS positive cells in the PVN (36% less) compared to sham rats. The number of NOS positive cells remained unaltered in the SON, MePO and LH in rats with HF. Conversely there was an increased number of NOS positive cells in the SFO (42% greater) and OVLT (100% greater). These data support the conclusion that the NO system within the hypothalamus involved in controlling autonomic outflow is altered during HF and may contribute to the elevated levels of vasopressin and sympatho-excitation commonly observed in HF.
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PMID:Altered number of diaphorase (NOS) positive neurons in the hypothalamus of rats with heart failure. 955 24

We have demonstrated a decreased neuronal nitric oxide (NO) synthase (nNOS) message in the hypothalamus of rats with heart failure (HF). Subsequently, we have demonstrated that NADPH diaphorase (a commonly used marker for nNOS activity) positive neurons are decreased in paraventricular nucleus (PVN) of rats with coronary artery ligation model of HF. The goal of the present study was to examine the influence of endogenous NO within the PVN on renal sympathetic nerve discharge (RSND) during HF. In alpha-chloralose- and urethane-anesthetized rats, an inhibitor of NO synthase, N(G)-monomethyl-L-arginine (L-NMMA) microinjected into the PVN (50, 100, and 200 pmol in 50-200 nl) produced a dose-dependent increase in RSND, blood pressure, and heart rate in control and HF rats. These responses were attenuated in rats with HF compared with control rats. On the other hand, the NO agonist, sodium nitroprusside, microinjected in PVN produced a dose-dependent decrease in RSND and blood pressure in control and HF rats. These responses were less in rats with HF compared with control rats. These data suggest that the endogenous NO-mediated effect within the PVN of HF rats is less potent in suppressing RSND compared with control rats. These data support the conclusion that the NO system within the PVN involved in controlling autonomic outflow is altered during HF and may contribute to the elevated levels of renal sympathoexcitation commonly observed in HF.
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PMID:Blunted nitric oxide-mediated inhibition of renal nerve discharge within PVN of rats with heart failure. 1151 64

The paraventricular nucleus (PVN) of the hypothalamus is known to be involved in the control of sympathetic outflow. Nitric oxide (NO) has been shown to have a sympathoinhibitory effect in the PVN. The goal of the present study was to examine the influence of overexpression of neuronal NO synthase (nNOS) within the PVN on renal sympathetic nerve discharge (RSND). Adenovirus vectors encoding either nNOS (Ad.nNOS) or beta-galactosidase (Ad.beta-Gal) were transfected into the PVN in vivo. Initially, the dose of adenovirus needed for infection was determined from in vitro infection of cultured fibroblasts. In Ad.nNOS-treated rats, the local expression of nNOS within the PVN was confirmed by histochemistry for NADPH-diaphorase-positive neurons. There was a robust increase in staining of NADPH-diaphorase-positive cells in the PVN on the side injected with Ad.nNOS. The staining peaked at 3 days after injection of the virus. In alpha-chloralose- and urethane-anesthetized rats, microinjection of N(G)-monomethyl-L-arginine (L-NMMA), a NO antagonist, into the PVN produced a dose-dependent increase in RSND, blood pressure, and heart rate. There was a potentiation of the increase in RSND, blood pressure, and heart rate due to L-NMMA in Ad.nNOS-injected rats compared with Ad.beta-Gal-injected rats. These results suggest that the endogenous NO-mediated effect in the PVN of Ad.nNOS-treated rats is more effective in suppressing RSND compared with Ad.beta-Gal-treated rats. These observations support the contention that an overexpression of nNOS within the PVN may be responsible for increased suppression of sympathetic outflow. This technique may be useful in pathological conditions know to have increased sympathetic outflow, such as hypertension or heart failure.
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PMID:Effect of in vivo gene transfer of nNOS in the PVN on renal nerve discharge in rats. 1178 7

We hypothesized that gene transfer of neuronal nitric oxide synthase (nNOS) into the rostral ventrolateral medulla (RVLM) improves baroreflex function in rats with chronic heart failure (CHF). Six to eight weeks after coronary artery ligation, rats showed hemodynamic signs of CHF. A recombinant adenovirus, either Ad.nNOS or Ad.beta-Gal, was transfected into the RVLM. nNOS expression in the RVLM was confirmed by Western blot analysis, NADPH-diaphorase, and immunohistochemical staining. We studied baroreflex control of the heart rate (HR) and renal sympathetic nerve activity (RSNA) in the anesthetized state 3 days after gene transfer by intravenous injections of phenylephrine and nitroprusside. Baroreflex sensitivity was depressed for HR and RSNA regulation in CHF rats (2.0 +/- 0.3 vs. 0.8 +/- 0.2 beats.min-1.mmHg-1, P < 0.01 and 3.8 +/- 0.3 vs. 1.2 +/- 0.1% max/mmHg, P < 0.01, respectively). Ad.nNOS transfer into RVLM significantly increased the HR and RSNA ranges (152 +/- 19 vs. 94 +/- 12 beats/min, P < 0.05 and 130 +/- 16 vs. 106 +/- 5% max/mmHg, P < 0.05) compared with the Ad.beta-Gal in CHF rats. Ad.nNOS also improved the baroreflex gain for the control of HR and RSNA (1.8 +/- 0.2 vs. 0.8 +/- 0.2 beats.min-1.mmHg-1, P < 0.01 and 2.6 +/- 0.2 vs. 1.2 +/- 0.1% max/mmHg, P < 0.01). In sham-operated rats, we found that Ad.nNOS transfer enhanced the HR range compared with Ad.beta-Gal gene transfer (188 +/- 15 vs. 127 +/- 14 beats/min, P < 0.05) but did not alter any other parameter. This study represents the first demonstration of altered baroreflex function following increases in central nNOS in the CHF state. We conclude that delivery of Ad.nNOS into the RVLM improves baroreflex function in rats with CHF.
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PMID:nNOS gene transfer to RVLM improves baroreflex function in rats with chronic heart failure. 1296 83

Congestive heart failure (CHF) is characterized by impaired cardiovascular reflexes and increased neurohumoral drive. The long-term sympatho-excitation increases the progression and risk of mortality during CHF. The paraventricular nucleus (PVN) of the hypothalamus is a very important central site for integration of sympathetic outflow and cardiovascular function. Within the PVN, nitric oxide (NO), mainly generated by neuronal nitric oxide synthase (nNOS), functions in inhibitory regulation of sympathetic outflow. Our previous study has indicated that in rats with experimental heart failure, the NO mechanism within the PVN is attenuated. We hypothesize that this alteration may contribute to the sympatho-excitation commonly observed in CHF. To investigate the role of NO within the PVN in sympathetic dysfunction in CHF, we have manipulated nNOS expression using adenoviral gene transfer of nNOS or nNOS antisense. These techniques have allowed us to observe the effects of alterations in nNOS on sympathetic outflow and cardiovascular function. In this chapter, we describe the methods for delivering nNOS adenoviral vector or nNOS antisense into the PVN using microinjection, as well as the protocols for detecting nNOS expression after these manipulations, using Western blot, NADPH-diaphorase staining, and immunofluorescent staining.
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PMID:Manipulation of neuronal nitric oxide synthase within the paraventricular nucleus using adenovirus and antisense technology. 1601 11

Insufficient growth and rarefaction of capillaries, followed by endothelial dysfunction may represent one of the most critical mechanisms involved in heart damage. In this study we examined histochemical and ultrastructural changes in myocardial capillary endothelium in two models of heart failure streptozotocin-induced diabetes mellitus (STZ) and NO-deficient hypertension in male Wistar rats. Diabetes was induced by a single i.v. dose of STZ (45 mg/kg) and chronic 9-week stage was analysed. To induce NO-deficient hypertension, animals were treated with inhibitor of NO synthase L-nitroarginine methylester (L-NAME) (40 mg/kg) for 4 weeks. Left ventricular tissue was processed for enzyme catalytic histochemistry of capillary alkaline phosphatase (AlPh), dipeptidyl peptidase IV (DPP IV), and endothelial NO synthase/NADPH-diaphorase (NOS) and for ultrastructural analysis. In diabetic and hypertensive rats, lower/absent AlPh and DPP IV activities were found in focal micro-areas. NOS activity was significantly reduced and persisted only locally. Quantitative evaluation demonstrated reduction of reaction product intensity of AlPh, DPP and NOS by 49.50%, 74.36%, 20.05% in diabetic and 62.93%, 82.71%, 37.65% in hypertensive rats. Subcellular alterations of endothelial cells were found in heart of both groups suggesting injury of capillary function as well as compensatory processes. Endothelial injury was more significant in diabetic animals, in contrast the adaptation was more evident in hypertensive ones. CONCLUDING: both STZ-induced diabetes- and NO-deficient hypertension-related cardiomyopathy were accompanied by similar features of structural remodelling of cardiac capillary network manifested as angiogenesis and angiopathy. The latter was however, predominant and may accelerate disappearance of capillary endothelium contributing to myocardial dysfunction.
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PMID:Ultrastructure and histochemistry of rat myocardial capillary endothelial cells in response to diabetes and hypertension. 1604 16

Nitric oxide synthase (NOS) expression in human intracardiac ganglia was studied using two techniques--histochemical demonstration of NADPH-diaphorase and immunohistochemical staining for NOS. To detect the influence of coronary heart disease on NOS expression, hearts were studied in patients that died from heart failure (n = 8) and in persons that died in accidents (n = 3, control). It was found that human intracardiac neurons normally expressed mainly NOS1, and the proportion of these cells amounted to about 40%. A portion of neurons with low and moderate density of staining for NADPH-diaphorase was increased in ischemic myocardium, probably, due NOS2 induction.
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PMID:[Nitric oxide synthase in human intracardiac ganglia in the normal and ischemic myocardium]. 1711 56


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