Dietary Effects of Structured Lipids and Phytosteryl Esters on Cardiovascular Function in Spontaneously Hypertensive Rats
| Autor: | Byung Hee Kim, Stephen J. Lewis, Tom P. Robertson, Casimir C. Akoh, Kevin Sandock |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Male
Agonist medicine.medical_specialty Baroreceptor Normal diet medicine.drug_class Blood Pressure Vasodilation Baroreflex Cardiovascular System Random Allocation Heart Rate Rats Inbred SHR Internal medicine medicine Animals Phenylephrine Pharmacology Chemistry Phytosterols Dietary Fats Rats Endocrinology Hypertension cardiovascular system Arterial blood Endothelium Vascular Sodium nitroprusside Cardiology and Cardiovascular Medicine Sesame Oil circulatory and respiratory physiology medicine.drug |
| Zdroj: | Journal of Cardiovascular Pharmacology. 50:176-186 |
| ISSN: | 0160-2446 |
| DOI: | 10.1097/fjc.0b013e31805d8f03 |
| Popis: | This study examined the dietary effects of sesame oil (SO)-based structured lipids (SL) and phytosteryl esters (PE) on cardiovascular function in conscious spontaneously hypertensive rats (SHR) fed high-fat (HF) diets (20% w/w fat). The dietary groups were as follows: normal diet (4.5% w/w fat), SO, SO fortified with PE (SOP), SL, and SL fortified with PE (SLP). Mean arterial blood pressures were similar in all groups, whereas resting heart rates (HR) were higher in all HF-fed groups. The pressor responses to the alpha1-adrenoceptor agonist, phenylephrine (5 microg/kg), were similar in all groups. However, the pressor responses to phenylephrine (10 microg/kg) were diminished in SO- or SL-fed SHR, whereas they were not diminished in SOP- or SLP-fed SHR. The depressor responses elicited by the nitric oxide (NO) donor, sodium nitroprusside (5 and 10 microg/kg), were not diminished in HF-fed rats. Baroreflex-mediated changes in HR were variously decreased in the HF-fed groups, and this decrease tended to be greater in SOP and SLP than in SO and SL groups. The depressor and tachycardic responses elicited by the beta-adrenoceptor agonist, isoproterenol, were equivalent in all groups. The depressor responses elicited by the endothelium-dependent agonist, acetylcholine (0.1 microg/kg), and the hypertension elicited by the NO synthesis inhibitor, NG-nitro-L-arginine methylester (25 micromol/kg), were similar in all groups. These findings demonstrate that (1) HF diets increase resting HR and impair baroreflex function in SHR, whereas they do not obviously affect endothelium-dependent vasodilation, and (2) fortification with PE may be deleterious to cardiovascular function (eg, baroreflex activity) in SHR. |
| Databáze: | OpenAIRE |
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