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Perioperative sodium abnormalities or dysnatremia is not uncommon in patients presenting for cardiac surgery and is associated with increased morbidity and mortality. Both the disease process of heart failure and its treatment may contribute to abnormalities in serum sodium concentration. Serum sodium is the main determinant of serum osmolality, which in turn affects cell volume. Brain cells are particularly vulnerable to changes in serum osmolality because of the nondistensible cranium. The potentially catastrophic neurologic sequelae of rapidly correcting chronic dysnatremia and the time-sensitive nature of cardiac surgery can make the management of these patients challenging. The use of cardiopulmonary bypass to facilitate surgery adds another layer of complexity in the intraoperative management of sodium and water balance. This narrative review examines the definition and classification of dysnatremia. It also covers the etiology and pathophysiology of dysnatremia, implications during cardiac surgery requiring cardiopulmonary bypass, and the perioperative management of dysnatremia.
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Procedimientos Quirúrgicos Cardíacos , Hipernatremia , Hiponatremia , Sodio/sangre , Adulto , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Puente Cardiopulmonar/efectos adversos , Humanos , Hipernatremia/diagnóstico , Hipernatremia/etiología , Hiponatremia/diagnóstico , Hiponatremia/etiologíaRESUMEN
This review is to examine the current literatures on the relationship between periodontitis and hypertension as well as to explore the possible biological pathways underlying the linkage between these health conditions. Hypertension is one of the major risk factors for cardiovascular diseases. Oxidative stress and endothelial dysfunction are among the critical components in the development of hypertension. Inflammation has received much attention recently and may contribute to a pivotal role in hypertension. Periodontitis, a chronic low-grade inflammation of gingival tissue, has been linked to endothelial dysfunction, with blood pressure elevation and increased mortality risk in hypertensive patients. Inflammatory biomarkers are increased in hypertensive patients with periodontitis. Over the years, various researches have been performed to evaluate the involvement of periodontitis in the initiation and progression of hypertension. Many cross-sectional studies documented an association between hypertension and periodontitis. However, more well-designed prospective population trials need to be carried out to ascertain the role of periodontitis in hypertension.
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Hipertensión/epidemiología , Hipertensión/metabolismo , Mediadores de Inflamación/metabolismo , Estrés Oxidativo/fisiología , Periodontitis/epidemiología , Periodontitis/metabolismo , Animales , Estudios Transversales , Gingivitis/diagnóstico , Gingivitis/epidemiología , Gingivitis/metabolismo , Humanos , Hipertensión/diagnóstico , Periodontitis/diagnósticoRESUMEN
Chronic inflammation is the underlying mechanism for many diseases. Thus, inflammatory signaling pathways are valuable targets for new treatment modalities. Natural products have gained interest as a potential source of bioactive compounds which provide health benefits in combating inflammatory-related diseases. Recent reports have linked the medicinal values of Bixa orellana L. with its anti-inflammatory activities. Therefore, this review aims to examine the therapeutic potential of bixin, a major bioactive constituent found in the seeds of B. orellana, on inflammatory-related diseases based on existing in vitro and in vivo evidence. Additionally, the anti-inflammatory mechanism of bixin via signaling pathways is explored and possible toxic effects are addressed. The findings suggest that bixin may ameliorate inflammation via inhibition of toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB), phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) and thioredoxin-interacting protein/NOD-like receptor protein 3 (TXNIP/NLRP3) inflammasome mechanisms. More well-planned clinical studies should be performed to verify its effectiveness and safety profile.
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This study aimed to investigate the antibacterial activity of three endodontic sealers, AH Plus, iRoot SP, and EndoSeal MTA, against four planktonic bacteria species. The antibacterial activity of the three endodontic sealers was assessed using a modified direct contact test. Bacteria suspension of Actinomycoses viscosus, Enterococcus faecalis, Staphylococcus aureus, and Streptococcus mutans were left in contact with the sealers that were pre-set or set for 1, 3, 7, and l4 days for an hour. Freshly mixed AH Plus and EndoSeal MTA were highly effective against all four tested bacteria as no surviving bacteria were recovered after treatment. Meanwhile, freshly mixed iRoot SP was not able to kill all bacteria, regardless of the species, demonstrating a weak antibacterial effect. After 24 h, AH Plus lost its antibacterial activity. EndoSeal MTA showed a strong and extended bactericidal effect against S. aureus and S. mutans for 3 days and A. viscosus for 7 days. In conclusion, fresh AH Plus and EndoSeal MTA exhibited a potent effect against all four bacteria species. EndoSeal MTA remained effective after setting when tested against A. viscosus, S. aureus, and S. mutans. Among all tested sealers, iRoot SP demonstrates the weakest antibacterial activity.
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Cardiovascular diseases such as hypertension and atherosclerosis are the common causes of mortality in developed and developing countries. Repeated heating of the dietary oil is a common practice to reduce cost during food preparation. When the cooking oil is heated at high temperatures, production of free radicals augments the oxidative degradation of lipids and depletes the natural antioxidant contents of the cooking oil. Chronic intake of foods prepared using reheated oil could impair antioxidant capacity, leading to oxidative stress and inflammation. This review aims to summarize the current evidence of lipid oxidation products on hypertension and atherosclerosis via inflammatory pathway. In particular, toxic lipid oxidation products such as malondialdehyde and 4-hydroxy-2-nonenal are taken into account. Understanding the signaling pathways underlying the pathology associated with the lipid oxidation-derived aldehydes may be useful to develop therapeutic strategies for the prevention of inflammatory-related cardiovascular complications.
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Atherosclerosis poses serious health problems and increases the risk of various cardiovascular diseases, including myocardial infarction, heart failure, ischemic stroke, and peripheral arterial disease. Atherosclerosis patients require long-term medications to prevent complications, some of which are costly and may result in unwanted adverse reactions. Natural products have emerged as potential sources of bioactive compounds that provide health benefits in cardiovascular diseases. Increased inflammation and vascular remodeling have been associated with atherosclerosis pathogenesis. The molecules involved in signaling pathways are considered valuable targets for new treatment approaches. Therefore, this review aimed to summarize the available evidence of the anti-inflammatory effects of thymoquinone, the major active compound isolated from Nigella sativa L., via inflammatory signaling pathways in atherosclerosis. Specifically, nuclear factor-κB and mitogen-activated protein kinase signaling pathways were considered. Furthermore, the potential toxic effects elicited by thymoquinone were addressed. These findings suggest a potential role of thymoquinone in managing atherosclerosis, and further studies are required to ascertain its effectiveness and safety profile.
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BACKGROUND: Periodontitis is a noncommunicable inflammatory disease of the soft tissue and bone surrounding the teeth in the jaw, which affects susceptible individuals with poor oral hygiene. A growing interest has been seen in the use of dietary supplements and natural products for the treatment and prevention of periodontitis. Vitamin E consists of two major groups, namely tocopherols and tocotrienols, which are botanical lipophilic compounds with excellent anti-inflammatory and antioxidant properties. HIGHLIGHT: This review aimed to summarize the preclinical and clinical findings on the effects of vitamin E on periodontitis. The current literature suggests that vitamin E could improve the periodontal status by correcting redox status imbalance, reducing inflammatory responses, and promoting wound healing, thus highlighting the potential of vitamin E in the management of periodontitis. CONCLUSION: Direct evidence for the use of vitamin E supplementation or treatment of periodontitis in humans is still limited. More well-designed and controlled studies are required to ascertain its effectiveness.
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Periodontitis , Tocotrienoles , Antioxidantes/uso terapéutico , Suplementos Dietéticos , Humanos , Periodontitis/tratamiento farmacológico , Vitamina E/uso terapéuticoRESUMEN
BACKGROUND: Poor control of blood pressure leads to hypertension which is a major risk factor for development of cardiovascular disease. The present study aimed to explore possible mechanisms of elevation in blood pressure following consumption of heated vegetable oil. METHODS: Forty-two male Sprague-Dawley rats were equally divided into six groups: Group I (control)--normal rat chow, Group II--fresh soy oil, Group III--soy oil heated once, Group IV--soy oil heated twice, Group V--soy oil heated five times, Group VI--soy oil heated ten times. Blood pressure was measured at the baseline level and at a monthly interval for six months. Plasma nitric oxide, heme oxygenase and angiotensin-converting enzyme levels were measured prior to treatment, at month-three and month-six later. At the end of treatment, the rats were sacrificed and thoracic aortas were taken for measurement of vascular reactivity. RESULTS: Blood pressure increased significantly (p<0.01) in the repeatedly heated oil groups compared to the control and fresh soy oil groups. Consumption of diet containing repeatedly heated oil resulted higher plasma angiotensin-converting enzyme level and lower nitric oxide content and heme oxygenase concentration. Reheated soy oil groups exhibited attenuated relaxation in response to acetylcholine or sodium nitroprusside, and greater contraction to phenylephrine. CONCLUSION: As a result of consumption of repeatedly heated soy oil, an elevation in blood pressure was observed which may be due to the quantitative changes in endothelium dependent and independent factors including enzymes directly involved in the regulation of blood pressure.
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Calor/efectos adversos , Hipertensión/inducido químicamente , Peróxidos Lipídicos/toxicidad , Oxidantes/toxicidad , Aceite de Soja/química , Vasodilatación , Animales , Aorta Torácica/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Enfermedades Cardiovasculares/prevención & control , Dieta/efectos adversos , Relación Dosis-Respuesta a Droga , Manipulación de Alimentos , Hemo Oxigenasa (Desciclizante)/sangre , Hipertensión/sangre , Hipertensión/etiología , Técnicas In Vitro , Peróxidos Lipídicos/administración & dosificación , Masculino , Óxido Nítrico/sangre , Oxidantes/administración & dosificación , Peptidil-Dipeptidasa A/sangre , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Aceite de Soja/administración & dosificación , Aceite de Soja/toxicidad , Factores de Tiempo , Vasodilatación/efectos de los fármacosRESUMEN
Oxidization of dietary cooking oil increases the risk of cardiovascular diseases such as hypertension by increasing the formation oxidative oxygen radicals. The aim of study was to investigate the effects of repeatedly heated palm oil on blood pressure, plasma nitrites, and vascular reactivity. Nitrites were measured, as an indirect marker for nitric oxide production. Male Sprague-Dawley rats were divided into four groups: control group fed with basal diet and other three groups fortified with 15% weight/weight fresh palm oil (FPO), palm oil heated five times (5HPO) or palm oil heated ten times (10HPO) for 24 weeks. The oil was heated to 180 degrees C for 10 min. Blood pressure was measured at baseline and at intervals of four weeks for 24 weeks using non-invasive tail-cuff method. Following 24 weeks, the rats were sacrificed and thoracic aortas were dissected for measurement of vascular reactivity. Blood pressure was elevated significantly (p < 0.05) in 5HPO and 10HPO groups, with the 10HPO group showing higher values. Aortic rings from animals fed with heated oil showed diminished relaxation in response to acetylcholine or sodium nitroprusside, and greater contraction to phenylephrine. Acetylcholine and sodium nitroprusside cause endothelium-dependent and endothelium-independent relaxation, respectively. Relaxation responses remained unaltered in the FPO group, with the attenuated contractile response to phenylephrine, compared to control group. FPO increased plasma nitrites by 28%, whereas 5HPO and 10HPO reduced them by 25% and 33%, respectively. Intake of repeatedly heated palm oil causes an increase in blood pressure, which may be accounted for by the attenuated endothelium-dependent vasorelaxant response.
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Presión Sanguínea/efectos de los fármacos , Calor , Aceites de Plantas/química , Aceites de Plantas/farmacología , Vasodilatación/efectos de los fármacos , Acetilcolina/farmacología , Animales , Aorta/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Grasas Insaturadas en la Dieta/farmacología , Grasas Insaturadas/química , Masculino , Óxido Nítrico/sangre , Nitroprusiato/farmacología , Aceite de Palma , Fenilefrina/farmacología , Aceites de Plantas/administración & dosificación , Ratas , Ratas Sprague-Dawley , Vasoconstricción/efectos de los fármacosRESUMEN
Cardiovascular diseases (CVDs) such as angina, hypertension, myocardial ischemia, and heart failure are the leading causes of morbidity and mortality worldwide. One of the major transcription factors widely associated with CVDs is nuclear factor-kappa B (NFκB). NFκB activation initiates the canonical and non-conical pathways that promotes activation of transcription factors leading to inflammation, such as leukocyte adhesion molecules, cytokines, and chemokines. Flavonoids are bioactive polyphenolic compounds found abundantly in various fruits, vegetables, beverages (tea, coffee), nuts, and cereal products with cardiovascular protective properties. Flavonoids can be classified into six subgroups based on their chemical structures: flavanones, flavones, flavonols, flavan-3-ols, isoflavones, and anthocyanidins. As NFκB inhibitors, these flavonoids may modulate the expression of pro-inflammatory genes leading to the attenuation of the inflammatory responses underlying various cardiovascular pathology. This review presents an update on the anti-inflammatory actions of flavonoids via inhibition of NFκB mechanism supporting the therapeutic potential of these natural compounds in various CVDs.
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BACKGROUND: Palm oil used worldwide contains considerable amounts of antioxidants, namely, vitamin E and carotenes. The purpose of the study was to observe the effect of heated palm oil on blood pressure and observe the cardiac histological changes in rats. METHODS: Forty male Sprague Dawley rats were divided equally into four groups and given treatment as follows: (i) basal diet (control group); (ii) basal diet fortified with 15% weight/weight (w/w) fresh palm oil (FPO); (iii) basal diet fortified with 15% w/w palm oil heated five times (5HPO); (iv) basal diet fortified with 15% w/w palm oil heated ten times (10HPO). Treatment duration was 16 weeks. Blood pressure was measured at baseline and at monthly intervals for 4 months using the tail-cuff method. After 16 weeks of study, the rats were killed and the hearts were taken out. The specimens were sectioned longitudinally and stained with hematoxylin and eosin for light microscopy. RESULTS: The FPO group did not show any significant changes in blood pressure and histological study. There was a significant increase (p <0.05) in blood pressure in the 5HPO and 10HPO groups. However, blood pressure in the 10HPO group was higher than in the 5HPO group. Histological sections of the heart showed necrosis in cardiac tissue in the 5HPO and 10HPO groups with the latter group showing more damage. CONCLUSIONS: Fresh palm oil has no deleterious effects on blood pressure and cardiac tissue but prolonged consumption of repeatedly heated palm oil may result in an increase in blood pressure level with necrosis of cardiac tissue.
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Presión Sanguínea/efectos de los fármacos , Corazón/efectos de los fármacos , Aceites de Plantas/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Calor , Masculino , Miocardio/patología , Tamaño de los Órganos/efectos de los fármacos , Aceite de Palma , Ratas , Ratas Sprague-DawleyRESUMEN
Hypertension and atherosclerosis are among the most common causes of mortality in both developed and developing countries. Experimental animal models of hypertension and atherosclerosis have become a valuable tool for providing information on etiology, pathophysiology, and complications of the disease and on the efficacy and mechanism of action of various drugs and compounds used in treatment. An animal model has been developed to study hypertension and atherosclerosis for several reasons. Compared to human models, an animal model is easily manageable, as compounding effects of dietary and environmental factors can be controlled. Blood vessels and cardiac tissue samples can be taken for detailed experimental and biomolecular examination. Choice of animal model is often determined by the research aim, as well as financial and technical factors. A thorough understanding of the animal models used and complete analysis must be validated so that the data can be extrapolated to humans. In conclusion, animal models for hypertension and atherosclerosis are invaluable in improving our understanding of cardiovascular disease and developing new pharmacological therapies.
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Aterosclerosis/fisiopatología , Modelos Animales de Enfermedad , Hipertensión/fisiopatología , Animales , Aterosclerosis/genética , Humanos , Hipertensión/genéticaRESUMEN
Awake intubation with a flexible fibrescope is usually done electively in patients with a known difficult airway. Herein, we describe the case of an elective awake tracheal intubation that was performed on a patient with a large, obstructive supraglottic mass. The intubation was successfully performed using the Bonfils fibrescope after several failed attempts with a flexible fibrescope. This case highlights the usefulness of the Bonfils fibrescope and the limitations of the flexible fibrescope in certain clinical situations.
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Tecnología de Fibra Óptica , Intubación Intratraqueal/instrumentación , Intubación Intratraqueal/métodos , Neoplasias Laríngeas/diagnóstico , Laringoscopios , Vigilia , Humanos , Laringoscopía/instrumentación , Masculino , Persona de Mediana Edad , Tráquea , Traqueostomía/métodosRESUMEN
Cardiovascular disease (CVD) is one of the leading major causes of morbidity and mortality worldwide. It may result from the interactions between multiple genetic and environmental factors including sedentary lifestyle and dietary habits. The quality of dietary oils and fats has been widely recognised to be inextricably linked to the pathogenesis of CVD. Vegetable oil is one of the essential dietary components in daily food consumption. However, the benefits of vegetable oil can be deteriorated by repeated heating that leads to lipid oxidation. The practice of using repeatedly heated cooking oil is not uncommon as it will reduce the cost of food preparation. Thermal oxidation yields new functional groups which may be potentially hazardous to cardiovascular health. Prolonged consumption of the repeatedly heated oil has been shown to increase blood pressure and total cholesterol, cause vascular inflammation as well as vascular changes which predispose to atherosclerosis. The harmful effect of heated oils is attributed to products generated from lipid oxidation during heating process. In view of the potential hazard of oxidation products, therefore this review article will provide an insight and awareness to the general public on the consumption of repeatedly heated oils which is detrimental to health.
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Enfermedades Cardiovasculares , Culinaria , Grasas Insaturadas en la Dieta/efectos adversos , Calor , Aceites de Plantas/efectos adversos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/metabolismo , Grasas Insaturadas en la Dieta/análisis , Humanos , Aceites de Plantas/administración & dosificación , Aceites de Plantas/química , Factores de RiesgoRESUMEN
Cardiovascular disease (CVD) is one of the leading major causes of morbidity and mortality worldwide. It may result from the interactions between multiple genetic and environmental factors including sedentary lifestyle and dietary habits. The quality of dietary oils and fats has been widely recognised to be inextricably linked to the pathogenesis of CVD. Vegetable oil is one of the essential dietary components in daily food consumption. However, the benefits of vegetable oil can be deteriorated by repeated heating that leads to lipid oxidation. The practice of using repeatedly heated cooking oil is not uncommon as it will reduce the cost of food preparation. Thermal oxidation yields new functional groups which may be potentially hazardous to cardiovascular health. Prolonged consumption of the repeatedly heated oil has been shown to increase blood pressure and total cholesterol, cause vascular inflammation as well as vascular changes which predispose to atherosclerosis. The harmful effect of heated oils is attributed to products generated from lipid oxidation during heating process. In view of the potential hazard of oxidation products, therefore this review article will provide an insight and awareness to the general public on the consumption of repeatedly heated oils which is detrimental to health.
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Enfermedades Cardiovasculares/etiología , Aceites de Plantas/efectos adversos , Animales , Aterosclerosis/etiología , Dislipidemias/etiología , Calor , Humanos , Hipertensión/etiología , Inflamación/etiología , Estrés Oxidativo , Factores de Riesgo , Remodelación VascularRESUMEN
Hypertension increases the risk for a variety of cardiovascular diseases, including stroke, coronary artery disease, heart failure, and peripheral vascular disease. The increase in oxidative stress has been associated with the pathogenesis of hypertension. Increase of blood pressure is due to an imbalance between antioxidants defence mechanisms and free radical productions. Excessive production of reactive oxygen species reduces nitric oxide bioavailability leading to an endothelial dysfunction and a subsequent increase in total peripheral resistance. Hypertension can cause few symptoms until it reaches the advanced stage and poses serious health problems with lifelong consequences. Hypertensive patients are required to take drugs for life to control the hypertension and prevent complications. Some of these drugs are expensive and may have adverse reactions. Hence, it is timely to examine scientifically, complimentary therapies that are more effective and with minimal undesirable effects. Nigella sativa (NS) and its active constituents have been documented to exhibit antioxidant, hypotensive, calcium channel blockade and diuretic properties which may contribute to reduce blood pressure. This suggests a potential role of NS in the management of hypertension, and thus more studies should be conducted to evaluate its effectiveness.
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BACKGROUND: Oxidative stress is associated with the pathogenesis of cardiovascular diseases. The process of deep-fat frying in dietary cooking oil plays a role in the generation of free radicals. In this study, palm olein heated to 180 °C was tested for its effect on the activity of blood pressure-regulating enzymes and lipid peroxidation. METHODS: Forty-two adult male Sprague-Dawley rats were equally assigned into 6 groups.The first group was fed with normal rat chow as the control group, and the subsequent groups were fed with rat chow fortified with 15% weight/weight of the following: fresh palm olein, palm olein heated once, palm olein heated twice, palm olein heated 5 times, or palm olein heated 10 times. The duration of feeding was 6 months. Fatty acid analyses of oil were performed using gas chromatography. Peroxide values were determined using standard titration. Plasma was collected for biochemical analyses. RESULTS: Repeatedly heated palm olein increased the levels of peroxide, angiotensin-converting enzyme, and lipid peroxidation as well as reduced the level of heme oxygenase. Fresh palm olein and palm olein heated once had lesser effects on lipid peroxidation and a better effect on the activity of blood pressure-regulating enzymes than repeatedly heated palm olein. CONCLUSION: Repeatedly heated palm olein may negatively affect the activity of blood pressure-regulating enzymes and increase lipid peroxidation.
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OBJECTIVES: The goal of this study was to determine the possible mechanism that is involved in the blood pressure-raising effect of heated vegetable oils. METHODS: Adult male Sprague-Dawley rats were divided into 11 groups; the control group was fed with rat chow, and the other groups were fed with chow that was mixed with 15% weight/weight palm or soy oils, which were either in a fresh form or heated once, twice, five, or ten times. Blood pressures were measured at the baseline and throughout the 24-week study. Plasma nitric oxide levels were assessed prior to treatment and at the end of the study. Following 24 weeks, the rats were sacrificed to investigate their vascular reactivity using the thoracic aorta. RESULTS: Palm and soy oils had no detrimental effects on blood pressure, and they significantly elevated the nitric oxide contents and reduced the contractile responses to phenylephrine. However, trials using palm and soy oils that were repeatedly heated showed an increase in blood pressure, enhanced phenylephrine-induced contractions, reduced acetylcholine- and sodium nitroprusside-induced relaxations relative to the control and rats that were fed fresh vegetable oils. CONCLUSIONS: The blood pressure-raising effect of the heated vegetable cooking oils is associated with increased vascular reactivity and a reduction in nitric oxide levels. The chronic consumption of heated vegetable oils leads to disturbances in endogenous vascular regulatory substances, such as nitric oxide. The thermal oxidation of the cooking oils promotes the generation of free radicals and may play an important contributory role in the pathogenesis of hypertension in rats.
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Aorta Torácica/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Calor , Aceites de Plantas/farmacología , Aceite de Soja/farmacología , Acetilcolina/farmacología , Animales , Aorta Torácica/fisiología , Endotelio Vascular/fisiología , Masculino , Óxido Nítrico/análisis , Nitroprusiato/farmacología , Aceite de Palma , Ratas , Ratas Sprague-Dawley , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacosRESUMEN
OBJECTIVES: The goal of this study was to determine the possible mechanism that is involved in the blood pressureraising effect of heated vegetable oils. METHODS: Adult male Sprague-Dawley rats were divided into 11 groups; the control group was fed with rat chow, and the other groups were fed with chow that was mixed with 15 percent weight/weight palm or soy oils, which were either in a fresh form or heated once, twice, five, or ten times. Blood pressures were measured at the baseline and throughout the 24-week study. Plasma nitric oxide levels were assessed prior to treatment and at the end of the study. Following 24 weeks, the rats were sacrificed to investigate their vascular reactivity using the thoracic aorta. RESULTS: Palm and soy oils had no detrimental effects on blood pressure, and they significantly elevated the nitric oxide contents and reduced the contractile responses to phenylephrine. However, trials using palm and soy oils that were repeatedly heated showed an increase in blood pressure, enhanced phenylephrine-induced contractions, reduced acetylcholine- and sodium nitroprusside-induced relaxations relative to the control and rats that were fed fresh vegetable oils. CONCLUSIONS: The blood pressure-raising effect of the heated vegetable cooking oils is associated with increased vascular reactivity and a reduction in nitric oxide levels. The chronic consumption of heated vegetable oils leads to disturbances in endogenous vascular regulatory substances, such as nitric oxide. The thermal oxidation of the cooking oils promotes the generation of free radicals and may play an important contributory role in the pathogenesis of hypertension in rats.