Effect of external iron and arsenic species on chelant-enhanced iron bioavailability and arsenic uptake in rice (Oryza sativa L.).

This study was conducted to investigate the effect of external iron status and arsenic species on chelant-enhanced iron bioavailability and arsenic uptake. Rice seedlings (Oryza sativa L.) were used as model plant, and were grown in artificially contaminated sandy soils irrigated with Murashige and Skoog (MS) culture solution. Arsenate uptake in roots and shoots of rice seedlings were affected significantly (p>0.05) while dimethylarsinic acid (DMAA) was not by the additional iron and chelating ligand treatments. Regardless of iron concentrations in the soil solution, HIDS increased arsenic uptake for roots more than EDTA and EDDS. Chelating ligands and arsenic species also influenced iron uptake in rice roots. Irrespective of arsenic species, HIDS was found to be more effective in the increase of iron bioavailability and uptake in rice roots compared to other chelants. There was a significant positive correlation (r=0.78, p<0.05) between arsenate and iron concentrations in the roots of rice seedlings grown with or without additional iron indicating that arsenate inhibit iron uptake. In contrast, there was no correlation between iron and DMAA uptake in roots. Poor correlation between iron and arsenic in shoots indicated that iron uptake in shoots was neither affected by additional iron nor by arsenic species. Compared to the control, chelating ligands increased iron uptake in shoots of rice seedlings significantly (p<0.05). Regardless of additional iron and arsenic species, iron uptake in rice shoots did not differed among EDTA, EDDS, and HIDS treatments.

Intraoperative administration of inhaled carbon monoxide reduces delayed graft function in kidney allografts in Swine.

Ischemia/reperfusion injury and delayed graft function (DGF) following organ transplantation adversely affect graft function and survival. A large animal model has not been characterized. We developed a pig kidney allograft model of DGF and evaluated the cytoprotective effects of inhaled carbon monoxide (CO). We demonstrate that donor warm ischemia time is a critical determinant of DGF as evidenced by a transient (4-6 days) increase in serum creatinine and blood urea nitrogen following transplantation before returning to baseline. CO administered to recipients intraoperatively for 1 h restored kidney function more rapidly versus air-treated controls. CO reduced acute tubular necrosis, apoptosis, tissue factor expression and P-selectin expression and enhanced proliferative repair as measured by phosphorylation of retinol binding protein and histone H3. Gene microarray analyses with confirmatory PCR of biopsy specimens showed that CO blocked proinflammatory gene expression of MCP-1 and heat shock proteins. In vitro in pig renal epithelial cells, CO blocks anoxia-reoxygenation-induced cell death while promoting proliferation. This large animal model of DGF can be utilized for testing therapeutic strategies to reduce or prevent DGF in humans. The efficacy of CO on improving graft function posttransplant validates the model and offers a potentially important therapeutic strategy to improve transplant outcomes.

Platelet transfusions in adult patients with particular reference to patients undergoing surgery.

Descriptive information on platelet (PLT) recipients, particularly during surgery, is limited. A description of the current epidemiology of PLT-transfused patients is required to optimize platelet transfusion care and to follow trends in PLT use. In 2004 and 2005, information was combined from several computerized medical systems. Participating hospitals (9 hospital districts of 21) handled approximately 64% of annual Finnish hospital admissions. A total of 6321 adult patients were transfused with 37,761 PLT products. Most PLT products (43.1%) were transfused to patients suffering from haematological malignancies. Only 1.0% of all surgical patients received PLTs (53.8% of PLT recipients and 35.8% of transfused PLTs). The most common single operation connected with PLT transfusion was coronary artery bypass while 27.1% of surgery-related PLTs were given to patients having an operation involving the digestive system or spleen. Only 36.4% of all PLT-transfused (operated and conservatively treated) patients were discharged directly home; in-hospital mortality was 9.5%. PLTs were given 40 products per 1000 hospital admissions requiring an operation in 2004, and 38 products in 2005. Perioperative PLT use is slightly decreasing in adult patients. As a single-operation type, coronary artery bypass patients receive most of the PLT products and have experienced no decline in PLT use over the years. Overall, PLT recipients have high in-hospital mortality.

Ethanol induces apoptosis in human mast cells.

AIMS: Alcohol abuse is associated with increased frequency of infections attributed to ethanol-induced immune suppression. The precise mechanism of immune suppression is however not known. Mast cells (MC) belong to the innate immune system and they have been implicated in the first line of immune defence against bacteria and parasites. Therefore we studied the effects of ethanol and its first metabolite acetaldehyde on mast cell viability, proliferation and apoptosis. MAIN METHODS: Human mast cell line (HMC)-1 cells, mouse bone marrow derived mast cells (mBMMC) and human peripheral blood derived mast cells (HuMC) were used. Effects of ethanol and acetaldehyde on mast cell proliferation were determined by assessing incorporation of [(3)H]thymidine into cellular DNA and by trypan blue exclusion. Apoptosis was assessed by measuring apoptotic nucleosomes and caspase-3, -8 and -9 activities using ELISA and by using Tunel assay. The expression of anti- and proapoptotic proteins Bcl-2 and Bax was analyzed by RT-PCR and western blot, respectively. KEY FINDINGS: Ethanol, but not acetaldehyde inhibited dose-dependently the proliferation and viability HMC-1 and mBMMC cells. The decreased viability was caused by apoptotic cell death of the MC. Significant apoptosis of HMC-1 cells was observed in the presence of 43mM (2.5 per thousand) ethanol. Induction of apoptosis was associated with clearly increased caspase-3 activity and moderately increased caspase-8 and 9 activities. Ethanol also shifted the Bcl-2/Bax balance towards apoptosis. SIGNIFICANCE: The ethanol-induced reduction of MC viability could contribute to immunosuppression associated with ethanol abuse.

Hydroxyiminodisuccinic acid (HIDS): A novel biodegradable chelating ligand for the increase of iron bioavailability and arsenic phytoextraction.

The influence of biodegradable chelating ligands on arsenic and iron uptake by hydroponically grown rice seedlings (Oryza sativa L.) was investigated. Even though the growth solution contained sufficient Fe, the growth of rice seedlings gradually decreased up to 76% with the increase of pH of the solution from 7 to 11. Iron forms insoluble ferric hydroxide complexes at neutral or alkaline pH in oxic condition. Chelating ligands produce soluble 'Fe-ligand complex' which assist Fe uptake in plants. The biodegradable chelating ligand hydroxyiminodisuccinic acid (HIDS) was more efficient then those of ethylenediaminetetraacetic acid (EDTA), ethylenediaminedisuccinic acid (EDDS), and iminodisuccinic acid (IDS) in the increase of Fe uptake and growth of rice seedling. A total of 79+/-20, 87+/-6, 116+/-15, and 63+/-18mg dry biomass of rice seedlings were produced with the addition of 0.5mM of EDDS, EDTA, HIDS, and IDS in the nutrient solution, respectively. The Fe concentrations in rice tissues were 117+/-15, 82+/-8, 167+/-25, and 118+/-22micromolg(-1) dry weights when 0.25mM of EDDS, EDTA, HIDS, and IDS were added to the nutrient solution, respectively. Most of the Fe accumulated in rice tissues was stored in roots after the addition of chelating ligands in the solution. The results indicate that the HIDS would be a potential alternative to environmentally persistent EDTA for the increase of Fe uptake and plant growth. The HIDS also increased As uptake in rice root though its translocation from root to shoot was not augmented. This study reports HIDS for the first time as a promising chelating ligand for the enhancement of Fe bioavailability and As phytoextraction.

Arsenic uptake by aquatic macrophyte Spirodela polyrhiza L.: interactions with phosphate and iron.

The uptake of arsenate (As(V)) and dimethylarsinic acid (DMAA) by aquatic macrophyte Spirodela polyrhiza L. was investigated to determine the influence of arsenic interaction with PO4(3-) and Fe ions. Plants were grown hydroponically on standard Murashige and Skoog (MS) culture solutions. Arsenic concentrations in Fe-oxide (Fe-plaque) on plant surfaces were determined by citrate-bicarbonate-ethylenediaminetetraacetic acid (CBE) technique. S. polyrhiza L. accumulated 51-fold arsenic from arsenate solution compared to that from DMAA solution with initial concentrations of 4.0 and 0.02microM of arsenic and phosphate, respectively. The arsenate uptake was negatively (p<0.001) correlated with phosphate uptake and positively (p<0.05) correlated with iron uptake. About 56% of the total arsenic was accumulated into the plant tissues while 44% was adsorbed on Fe-plaque (CBE-extract), when the plants were grown on arsenate solution. The DMAA uptake into the plant was neither affected by the phosphate concentrations nor correlated (p>0.05) with iron accumulation. The results suggest that adsorption of arsenate on Fe-plaque of the surface of S. polyrhiza L. contributes to the arsenic uptake significantly. Thus, arsenate uptake in S. polyrhiza L. occurred through the phosphate uptake pathway and by physico-chemical adsorption on Fe-plaques of plant surfaces as well. The S. polyrhiza L. uses different mechanisms for DMAA uptake.

Perioperative tobacco use interventions in Japan: a survey of thoracic surgeons and anaesthesiologists.

BACKGROUND: Tobacco use interventions in surgical patients who smoke could benefit both their short-term outcome and long-term health. Anaesthesiologists and surgeons can play key roles in delivering these interventions. This study determined the practices, attitudes, and beliefs of these physicians regarding tobacco use interventions in Japan. METHODS: Questionnaires were mailed to a national random sampling of Japanese anaesthesiologists and thoracic surgeons (1000 in each group). RESULTS: The survey response rate was 62%. More than 80% of respondents agreed or strongly agreed with the statements affirming the benefits of abstinence to surgical patients. However, only 26% of surgeons and 6% of anaesthesiologists reported almost always providing help to their patients to quit smoking. Compared with anaesthesiologists, surgeons were more likely to perform the elements of current recommendations for brief intervention, and to have attitudes favourable to tobacco use interventions. The most significant barrier to intervention identified by both groups was a lack of time to perform counselling. Compared with non-smokers, physicians who smoked were less likely to perform each of the recommended tobacco interventions CONCLUSIONS: Although current rates of intervention provided by anaesthesiologists and surgeons are low, there is considerable interest among these physicians in learning more about interventions. Given the relatively high prevalence of smoking in Japan and the potential for surgery to serve as a 'teachable moment' to promote abstinence from smoking, leadership by these specialists in the area of tobacco control could have a major impact on public health in Japan.

Estudo de confiabilidade da aplicação da escala de Fugl-Meyer no Brasil / Reliability study on the application of the Fugl-Meyer scale in Brazil

OBJETIVOS: Os objetivos do estudo foram realizar uma versão brasileira da escala original de Fugl-Meyer e verificar a confiabilidade da aplicação inter e intra-observador desta versão em pacientes crônicos pós AVC. MÉTODO: Participaram do estudo 50 pacientes portadores de hemiparesia, os quais foram submetidos a duas avaliações (confiabilidade intra-observador), realizadas por três fisioterapeutas (confiabilidade interobservador), procedentes de três centros de reabilitação. RESULTADOS: Os resultados demonstraram alta confiabilidade inter e intra-observador da EFM total (IC = 0,99 e 0,98; respectivamente), assim como para todas as subescalas (interobservador IC = 0,99 a 0,94; intra-observador IC = 0,98 a 0,87). CONCLUSÃO: Conclui-se neste artigo que não foi verificado conflitos de interpretação na versão brasileira da escala de Fugl-Meyer. Obtivemos alto índice de confiabilidade, tanto intra como interobservador, permitindo assim seu uso como instrumento de avaliação clínica e de pesquisa no Brasil.

Inhibition of c-kit tyrosine kinase by imatinib mesylate induces apoptosis in mast cells in rheumatoid synovia: a potential approach to the treatment of arthritis.

BACKGROUND: Mast cells have been implicated in the pathogenesis of arthritis, but elucidation of their precise role has been hampered by a lack of efficient and selective inhibitors of their function. OBJECTIVE: To elucidate the role of mast cells in the pathogenesis of rheumatoid arthritis (RA) and to assess whether apoptosis of cultured and synovial tissue mast cells can be induced by inhibiting mast cell growth factor receptor, c-kit tyrosine kinase. METHODS AND RESULTS: Double staining with tumour necrosis factor (TNF) alpha and tryptase antibodies showed the presence of TNFalpha positive mast cells in human rheumatoid synovial tissue. Selective activation of mast cells by anti-IgE resulted in production of TNFalpha in synovial tissue cultures. Inhibition of the c-kit tyrosine kinase with imatinib mesylate (1.0-10 micromol/l) induced profound apoptosis in cultured mast cells as judged by typical apoptotic morphology, increased number of apoptotic nucleosomes, and activation of caspases 8 and 9. Importantly, imatinib also induced apoptosis of mast cells in explant cultures of synovial tissue obtained from patients with RA as judged by a TUNEL assay. Inhibition of c-kit tyrosine kinase was accompanied by significant reduction of TNFalpha production in synovial tissue cultures. CONCLUSION: Mast cells may have a role in the pathogenesis of RA, and inhibition of c-kit may be a new means of inhibiting mast cell activity and of abrogating the contribution of mast cells to synovial inflammation in RA.

Serum levels of amidated gastrin-17 and pepsinogen I in atrophic gastritis: an observational case-control study.

BACKGROUND: Helicobacter pylori infection is often diagnosed with non-endoscopic methods, such as serology or breath or antigen stool tests. These tests provide information on the presence or absence of the H. pylori gastritis only. We investigated whether atrophic gastritis can be diagnosed and typed non-endoscopically if the serum levels of pepsinogen I (S-PGI) and gastrin-17 (S-G-17) are assayed in connection with H. pylori testing. METHODS: The present investigation is an observational case-control study comprising 100 selected dyspeptic outpatients with (cases) or without (controls) advanced (moderate or severe) atrophic gastritis. Before the blood tests, all patients underwent a diagnostic gastroscopy with multiple biopsies. The series of cases includes 56 patients. Eight had an advanced antrum limited atrophic gastritis, 13 had resected antrum (in two of whom the corpus mucosa in the stump was atrophic), and 30 had corpus-limited atrophic gastritis. Four patients had an advanced atrophic gastritis in both the antrum and corpus (multifocal atrophic gastritis), and the whole stomach was removed in one patient. Twenty of the 44 controls had a non-atrophic H. pylori gastritis. Both the antrum and corpus were normal and healthy in 24 patients. The S-PGI and S-G-17 were determined with EIA methods using monoclonal antibodies to PGI and amidated G-17. Postprandial S-G-17 (S-G-17prand) was measured 20 min after a protein-rich drink. The H. pylori antibodies were assayed with a polyclonal EIA method. RESULTS: A low S-PGI (<25 microg/l; an empirical cut-off with best discrimination) was found in 31 of 37 patients (84%) with and in 3 of 63 patients (5%) without corpus atrophy in the biopsy specimens. A low S-G-17prand (<5 pmol/l) was found in all 8 patients with H. pylori-associated antral atrophy and in 11 of 14 patients (79%) with resected antrum but in 3 of 20 control patients (15%) with H. pylori-related non-atrophic gastritis. Median and mean values of both S-G-17prand and S-PGI decreased with increasing grade of antral and corpus atrophy, respectively. Among all patients with atrophic gastritis (multifocal atrophic gastritis, or atrophic gastritis limited to antrum or corpus) or resected stomach, 50 of 56 patients (89%; Cl 95%: 81%-97%) had a low S-PGI and/or a low S-G-17prand with positive H. pylori serology. Such low values werc found in 3 of the 44 control patients (7%; CI 95%: 0%-14%). CONCLUSIONS: Low serum levels of G-17prand and PGI are conceivable biomarkers of atrophic antral and corpus gastritis, respectively. A low S-G-17prand is a sign of the multifocal or antrum-limited atrophic gastritis in patients infected with H. pylori.

Estimulacao eletrica neuromuscular e exercicios com movimentos na diagonal para ganho de forca em biceps e triceps braquial / Neuromuscular electrical stimulation and diagonal exercises to incremental of strength in biceps and triceps braquial

O proposito deste estudo foi avaliar os efeitos do exercicio contra-resistido em diagonal com halter e da estimulacao eletrica neuromuscular(EENM) combinada com exercicio isometrico ou combinada com exercicio contra-resistido em diagonal com halter no inremento de forca e no aumento de massa nos musculos biceps e triceps braquial. Para isso, 28 individuos de ambos os sexos foram divididos em quatro grupos (n=7 cada): grupo I - exercicios contra-resistidos em diagonal com halter; grupo II - EENM associado a isomtria; grupo III - exercicio contra-resistido em diagonal com halter associado a EENM; e o grupo IV - controle. Todos os voluntarios foram submetidos a um teste incremental de membros superiores (TIMS) com movimentos em diagonal, seguindo os principios do metodo de facilitacao neuromuscular proprioceptiva(FNP). Foram controladas, nesse teste, as seguintes variaveis: esforco de membros superiores(Escala de Borg), pressao arterial (PA), frequencia cardiaca (FC), perimetria e tempo em que o voluntario realizou o teste e a carga em que terminou. Apos 24 sessoes de treinamento, realizadas tres vezes por semana com a carga fixa de 50 por cento da carga maxima obtida no TMS, foi repetida a avaliacao. Diferencas significativas (p<0,05) foram encontradas na carga e no tempo pos-treinamento no grupo III e no aumento da perimetria no membro superior esquerdo do grupo I. Nao houve diferenca significativa para Escala de Borg entre os grupos, sugerindo a necessidade de mais pesuisas na area

Dissociation of hemopoietic chimerism and allograft tolerance after allogeneic bone marrow transplantation.

Creation of stable hemopoietic chimerism has been considered to be a prerequisite for allograft tolerance after bone marrow transplantation (BMT). In this study, we demonstrated that allogeneic BMT with bone marrow cells (BMC) prepared from either knockout mice deficient in both CD4 and CD8 T cells or CD3E-transgenic mice lacking both T cells and NK cells maintained a high degree of chimerism, but failed to induce tolerance to donor-specific wild-type skin grafts. Lymphocytes from mice reconstituted with T cell-deficient BMC proliferated when they were injected into irradiated donor strain mice, whereas lymphocytes from mice reconstituted with wild-type BMC were unresponsive to donor alloantigens. Donor-specific allograft tolerance was restored when donor-type T cells were adoptively transferred to recipient mice given T cell-deficient BMC. These results show that donor T cell engraftment is required for induction of allograft tolerance, but not for creation of continuous hemopoietic chimerism after allogeneic BMT, and that a high degree of chimerism is not necessarily associated with specific allograft tolerance.

Long-term treatment with neutral endopeptidase inhibitor improves cardiac function and reduces natriuretic peptides in rats with chronic heart failure.

OBJECTIVE: Increased secretion of atrial and brain natriuretic peptide (ANP and BNP) from hearts is known to exhibit favorable effects in patients and animals with heart failure, and inhibition of neutral endopeptidase (NEP), an enzyme that degrades ANP and BNP, may further increase these peptide levels. However, it is still unknown whether such elevation of the ANP and BNP may offer a therapeutic benefit to the progression of chronic heart failure (CHF). We examined the effects of ONO-9902, a novel NEP inhibitor, on changes in hemodynamic parameters, NEP activity and neurohumoral factors in rats with CHF induced by left coronary artery ligation (CAL). METHODS: Male Wistar rats (220-240 g) were subjected to induction of acute myocardial infarction by CAL. Rats were orally treated with ONO-9902 (300 mg/kg/day) from the 1st to 6th week after the operation. Hemodynamic and/or biochemical assessments were performed at the 1st and 6th weeks after the operation. RESULTS: A single administration of ONO-9902 inhibited the plasma and kidney NEP activities and thereby further augmented the elevation of plasma ANP concentration in rats with CAL at the 1st week after the operation. In rats with CAL at the 6th week after the operation, the left ventricular end-diastolic pressure (LVEDP) increased and cardiac output index (COI) decreased as compared with those of sham-operated rats. These changes were accompanied by marked increases in the plasma ANP, BNP and endothelin-1 (ET-1). Chronic treatment with ONO-9902 attenuated the increase in LVEDP and the decrease in COI. These changes were associated with a decrease in plasma ANP, BNP and ET-1 concentrations. CONCLUSIONS: The results suggest that chronic treatment with NEP inhibitor improves depressed cardiac function in rats with CHF. ONO-9902 may offer a new and possible therapeutic approach in patients with CHF.

Ethanol infusion increases ANP and p21 gene expression in isolated perfused rat heart.

Whether alcohol-induced heart failure is caused by a direct toxic effect of ethanol, metabolites, or whether it is a secondary result of neurohumoral, hormonal, or nutritional factors is not clear. To address this question a Langendorff retrograde coronary perfusion model of rat heart was used to study the effect of 0.5% (v/v) ethanol (n = 7) and 0.5 mM acetaldehyde (n = 9) on left ventricular expression of ANP, BNP, p53, p21, TNF-alpha,bax, bcl-2 as well as on DNA-fragmentation. Ethanol infusion of 150 min duration significantly induced both ANP and p21 mRNA expression of ventricular myocardium compared with hearts infused with vehicle (n = 8). Acetaldehyde did not exert any significant effects on any of the parameters studied, although the mean expression of TNF-alpha tended to be lower in the acetaldehyde-treated hearts than in control hearts. No evidence of increased DNA-fragmentation was found in ethanol or acetaldehyde treated groups. We conclude that ethanol per se is capable of inducing genes associated with hypertrophy and impaired function of the heart whereas a significant apoptosis is not involved in the initial phase of alcohol-induced cardiac injury.

Ethanol inhibits IgE-induced degranulation and cytokine production in cultured mouse and human mast cells.

Activated mast cells (MC) can produce a wide variety of potent inflammatory mediators. Excessive alcohol consumption is known to lead to immune deficiency and propensity for pneumonias in particular. As MCs are important in the first line of defence of mucosal membranes we have studied the effect of ethanol (EtOH) on several MC functions. EtOH attenuated dose dependently IgE-induced degranulation of mouse bone marrow derived mast cells (mBMMC) as reflected by the release of granule associated beta-hexosaminidase (beta-hex). A mean of 26 +/- 7% inhibition of beta-hex release was observed in the presence of 5/1000 (86 mM) EtOH and nearly complete inhibition in the presence of 20/1000 (344 mM) ethanol. The IgE-induced degranulation of mBMMC cultured with EtOH for seven days was inhibited to a similar degree as the degranulation of mBMMC exposed to EtOH for only one hour. Inclusion of 5/1000 (86 mM) ethanol in the medium reduced tumour necrosis factor (TNF)-alpha and interleukin (IL)-8 production in human mast cell line (HMC-1) cells by 55 +/- 7% and 19 +/- 5%, respectively, and the presence of 20/1000 (344 mM) ethanol inhibited the expression 81 +/- 12% and 59 +/- 14% respectively. These results suggest that, in contrast to previous assumption, ethanol inhibits several critical MC functions at least in vitro. This inhibition of mediator, and cytokine release in particular, could contribute to the immune deficiency associated with chronic alcohol consumption.

Effect of neutral endopeptidase inhibitor on endogenous atrial natriuretic peptide as a paracrine factor in cultured cardiac fibroblasts.

1. Cardiac remodelling is a fundamental response to hypertension, myocardial infarction and chronic heart failure, and involves cardiac fibroblast proliferation and production of extracellular matrix components such as collagen. The present study was performed to examine the role of endogenous atrial natriuretic peptide (ANP) as a possible paracrine factor for cardiac fibroblasts, and to examine the effects of three neutral endopeptidase (NEP) inhibitors, thiorphan, phosphoramidon and ONO-BB-039-02 (ONO-BB) on endogenous ANP-induced changes in collagen synthesis by cultured neonatal rat cardiac fibroblasts. 2. Each NEP inhibitor singly had no significant effect on collagen synthesis by cardiac fibroblasts, except for maximum concentration (10(-3) M) of thiorphan. 3. Exogenous ANP inhibited collagen synthesis in a concentration-dependent manner (10(-8) - 10(-6) M). Thiorphan (10(-4) and 10(-3) M) and phosphoramidon (10(-5) and 10(-4) M) enhanced the ANP (10(-7) M)-induced decrease in collagen synthesis. ONO-BB (10(-5) and 10(-4) M) slightly enhanced the ANP-induced decrease in collagen synthesis. 4. Myocyte-conditioned medium (MC-CM), as well as exogenous ANP, inhibited collagen synthesis dose-dependently. The decrease in collagen synthesis at 100% MC-CM was augmented by thiorphan (10(-3) M), phosphoramidon (10(-4) M) and ONO-BB (10(-4) M). 5. HS-142-1, a natriuretic peptide receptor antagonist, significantly reduced the MC-CM plus thiorphan- and MC-CM plus ONO-BB-induced decrease in collagen synthesis, by 92 and 62%, respectively and showed a tendency to attenuate the MC-CM plus phosphoramidon-induced decrease in collagen synthesis by 40%. 6. Our observations suggested that endogenous ANP released from cardiomyocytes inhibited collagen synthesis as a paracrine factor and that NEP inhibitors enhanced the activity of this peptide in cardiac fibroblasts.