title: Dietary effects of structured lipids and phytosteryl esters on cardiovascular function in spontaneously hypertensive rats.
abstract: 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.
authors: Department of Food Science and Technology, University of Georgia, Athens, Georgia 30602-7610, USA.
authors: Byung Hee
authors: BH
authors: Kim
authors: Kevin D
authors: KD
authors: Sandock
authors: Tom P
authors: TP
authors: Robertson
authors: Stephen J
authors: SJ
authors: Lewis
authors: Casimir C
authors: CC
authors: Akoh
mesh_terms: D000818:Animals; D017704:Baroreflex / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects* / Q000503:physiopathology; D004041:Dietary Fats / Q000009:adverse effects* / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D010840:Phytosterols / Q000009:adverse effects* / Q000494:pharmacology; D011897:Random Allocation; D051381:Rats; D011918:Rats, Inbred SHR; D012715:Sesame Oil / Q000009:adverse effects / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects
chemical_list: D004041:Dietary Fats; D010840:Phytosterols; D012715:Sesame Oil