Dietary omega 3 and omega 6 fatty acids and cardiovascular responses to pressor and depressor stimuli

Dietary n-3 polyunsaturated fatty acids affect the development of renovascular hypertension in rats

The consequences of a dietary n-3 PUFA supply was investigated on the blood pressure (BP) increase elicited by left renal artery stenosis in rats distributed in 3 groups (n = 8) fed for 8 weeks a semi-purified diet either as control diet or enriched diets (docosahexaenoic acid, DHA, or eicosapentaenoic acid, EPA). The PUFA intake induced large alterations in heart and kidney phospholipid fatty acid profile, but did not influence body weight, cardiac hypertrophy, renal left atrophy and right hypertrophy. Within 4 weeks, BP raised from 120-180 +/- 2 mm Hg in the control group, but only to 165 +/- 3 mm Hg in the n-3 PUFA groups. After stabilization of BP in the 3 groups, the rats received a short administration of increasing dose of perindopril. The lower dose (0.5 mg/kg) moderately decreased BP only in the control group. With higher doses (1, 5 and 10 mg/kg) BP was normalized in the 3 groups, with a higher amplitude of the BP lowering effect in the control group. A moderate n-3 PUFA intake can contribute to prevent the development of peripheral hypertension in rats by a mechanism that may involve angiotensin converting enzyme.

The membrane phospholipid hypothesis as a biochemical basis for the neurodevelopmental concept of schizophrenia

The neurodevelopmental hypothesis of schizophrenia is becoming an important feature of research in the field. However, its major drawback is that it lacks any biochemical basis which might draw the diverse observations together. It is suggested that the membrane phospholipid hypothesis can provide such a biochemical basis and that the neurodevelopmental phospholipid concept offers a powerful paradigm to guide future research.

Effects on blood pressure of omega 3 fats in subjects at increased risk of cardiovascular disease

This study was conducted to compare the effects of omega 3 fatty acids, taken as fish or fish-oil supplements in the setting of a high- or low-fat dietary background, on blood pressure and heart rate in men with moderate cardiovascular risks. One hundred twenty men were randomly allocated to five high-fat (40% of daily energy) and two low-fat (30% of energy) groups to undertaken a 12-week dietary intervention period involving fish, fish oil, or a combination of these. Sodium intake was restricted to less than 90 mmol/d. The five high-fat groups were assigned to take either 6 or 12 fish-oil capsules daily, fish or a combination of fish oil and fish, or placebo capsules. The two low-fat groups took either fish or placebo capsules. Fish meals were devised to provide 1.3 g of eicosapentaenoic acid daily, equivalent to that contained in 6 fish-oil capsules. Subjects were instructed to eat a selection of fish that provided an average of 3.65 g/d (range, 3.2 to 4.1 g/d) of total omega 3 fatty acids. Subjects were seen at regular intervals during the baseline and dietary intervention periods for measurement of weight, blood pressure, heart rate, dietary compliance, urinary electrolyte excretion, platelet phospholipid fatty acids, blood glucose, and insulin concentration. There was a greater fall in both systolic and diastolic blood pressures in subjects allocated fish or fish oil, particularly in the low-fat groups, compared with control subjects. However, there was no significant group effect.(ABSTRACT TRUNCATED AT 250 WORDS)