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Arterioscler Thromb Vasc Biol 1997 Jun;17(6):1163-1170 
Arterial compliance in obese subjects is improved with dietary plant n-3 fatty acid from flaxseed oil despite increased LDL oxidizability.
Nestel PJ, Pomeroy SE, Sasahara T, Yamashita T, Liang YL, Dart AM, Jennings GL, Abbey M, Cameron JD.
Baker Medical Research Institute, Prahran, VIC, Australia.

The compliance or elasticity of the arterial system, an important index of circulatory function, diminishes with increasing cardiovascular risk. 
Conversely, systemic arterial compliance improves through eating of fish and fish oil. 
We therefore tested the value of high intake of alpha-linolenic acid, the plant precursor of fish fatty acids. 
Fifteen obese people with markers for insulin resistance ate in turn four diets of 4 weeks each; saturated/high fat (SHF), alpha-linolenic acid/low fat (ALF), oleic/low fat (OLF), and SHF. Daily intake of alpha-linolenic acid was 20 g from margarine products based on flax oil. 
Systemic arterial compliance was calculated from aortic flow velocity and aortic root driving pressure. Plasma lipids, glucose tolerance, and in vitro LDL oxidizability were also measured. Systemic arterial compliance during the first and last SHF periods was 0.42 +/- 0.12 (mean +/- SD) and 0.56 +/- 0.21 units based on milliliters per millimeter of mercury. It rose significantly to 0.78 +/- 0.28 (P < .0001) with ALF; systemic arterial compliance with OLF was 0.62 +/- 0.19, lower than with ALF (P < .05). Mean arterial pressures and results of oral glucose tolerance tests were similar during ALF, OLF, and second SHF; total cholesterol levels were also not significantly different. However, insulin sensitivity and HDL cholesterol diminished and LDL oxidizability increased with ALF. 
The marked rise in arterial compliance at least with alpha-linolenic acid reflected rapid functional improvement in the systemic arterial circulation despite a rise in LDL oxidizability. Dietary n-3 fatty acids in flax oil thus confer a novel approach to improving arterial function.

Am J Clin Nutr 1986 Sep;44(3):336-40 
Does dietary linolenic acid influence blood pressure?
Berry EM, Hirsch J.

Short-term intervention studies have shown that diets rich in polyunsaturated fats have hypotensive properties. 
We have studied the long-term effects of dietary fat on blood pressure (BP) using adipose-tissue, fatty acid composition analysis in 399 free-living male subjects (average age, 47 yr).
Stepwise-regression analysis showed that adipose linoleic acid (18:2 n-6) was not associated with BP, whereas an absolute 1% increase in linolenic acid (18:3 n-3) (ALA) was associated with a decrease of 5 mm Hg in the systolic, diastolic, and composite mean arterial BP.
Linolenic acid (18:3) comprised only one-eighth the amount of linoleic acid (18:2)--the major polyunsaturate in adipose tissue and hence in the diet (2% vs 16%)--and yet it had a disproportionate association with BP.
This may be related to its role as a precursor for the production of prostaglandins and/or other vasoregulators. Dietary manipulation with n-3 fatty acids may be helpful in the treatment and prevention of hypertension.

Ann Med 1991 Aug;23(3):295-8 
Dietary fats, antioxidants and blood pressure.
Salonen JT.
Department of Community Health and General Practice, University of Kuopio, Finland.

Although obesity and alcohol intake as well as dietary sodium, potassium and magnesium are the major non-genetic determinants of blood pressure levels, interest has recently been stimulated in the function of fatty acids and antioxidants in the aetiology of hypertension. 
In the Kuopio Ischaemic Heart Disease Risk Factor Study both plasma ascorbic acid and serum selenium concentrations had a moderate, independent inverse association, 
estimated dietary intake of saturated fatty acids had a positive association and 
estimated dietary intake of linolenic acid had an inverse association with the mean resting blood pressure in 722 Eastern Finnish men with neither self reported hypertension nor cerebrovascular disease.
· Even though these cross sectional observations do not prove causality, they warrant clinical trials to verify or disprove that dietary fats and antioxidants are factors in the development of hypertension.

J Hypertens Suppl 1987 Dec;5(5):S521-4 
Vitamin C deficiency and low linolenate intake associated with elevated blood pressure: the Kuopio Ischaemic Heart Disease Risk Factor Study.
Salonen JT, Salonen R, Ihanainen M, Parviainen M, Seppanen R, Seppanen K, Rauramaa R.
Department of Community Health, University of Kuopio, Finland.

We investigated the association of dietary fatty acids and plasma antioxidative vitamins with blood pressure in 722 eastern Finnish men aged 54 years, examined in the Kuopio Ischaemic Heart Disease Risk Factor Study in 1984-1986, who had no known hypertension nor any cerebrovascular disease. 
Allowing for the major anthropometric, dietary, medical and psychological determinants of blood pressure in a multivariate regression analysis, plasma ascorbic acid concentration had a moderate, independent inverse association (P less than 0.0001) and the estimated dietary intake of linolenic acid an inverse (P = 0.026) independent association with mean resting blood pressure. 
The marked elevation of blood pressure at the lowest levels of plasma vitamin C concentration supports the hypothesis of the role of antioxidants in the aetiology of hypertension.

Med Hypotheses 1991 Sep;36(1):90-4 
Stress and fatty liver--possible indications for dietary long-chain n-3 fatty acids.
Singer P, Richter-Heinrich E.
Central Institute for Cardiovascular Research, Academy of Sciences of the GDR, Berlin-Buch, Germany.

The favourable effects of eicosapentaenoic acid (EPA)- and doco-sahexaenoic acid (DHA)-rich diets (marine fish, fish oil) on several risk factors for cardiovascular disease are well established. The present survey describes possible new indications for diets supplemented with long-chain n-3 fatty acids. 
During a standardized psychophysiological stress test (arithmetic, sentence completion tasks) systolic blood pressure after 2 weeks of diets supplemented with either 60 ml/day of sunflower or linseed oil was significantly decreased. 
During the sunflower oil-rich diet 45 g/day of linoleic acid (LA) and during the linseed oil-rich period 38 g/day of alpha-linolenic acid (LNA) were ingested. 
After a 2-week diet supplemented with mackerel (2 cans/day equivalent to 2.2 g/day of EPA and 2.8 g/day of DHA) systolic and diastolic blood pressure within the same test design appeared significantly lower. 
After a herring diet providing 2 cans/day, equivalent to 1.0 g of EPA and 1.8 g of DHA, the blood pressure-lowering effect was minor. 
The increase of thromboxane B2 (TxB2) during the stress test failed to occur after the fish diets. 
The results suggest a stress-protective effect of polyenoic acid-rich diets, which appears most pronounced and dose-related after long-chain n-3 fatty acids. 
In human liver an increase of fat droplet size in hepatocytes is associated with a decrease of the percentage of EPA in liver triglycerides. 
A diminution of plasma free fatty acids (FFA) after a mackerel diet might contribute to a depressed synthesis of liver triglycerides.(ABSTRACT TRUNCATED AT 250 WORDS)

Am J Epidemiol 1999 Sep 1;150(5):492-500 
Plasma fatty acid composition and 6-year incidence of hypertension in middle-aged adults: the Atherosclerosis Risk in Communities (ARIC) Study.
Zheng ZJ, Folsom AR, Ma J, Arnett DK, McGovern PG, Eckfeldt JH.
Department of Preventive Medicine, University of Kentucky Chandler Medical Center, Lexington, USA.

The association of baseline fatty acid composition in plasma cholesterol esters with 6-year incidence of hypertension was examined in middle-aged Minneapolis participants of the Atherosclerosis Risk in Communities (ARIC) Study (1987-1995). 
Compared with those who were never hypertensive (n = 1,975), incident hypertensives (n = 413) had statistically significantly higher baseline levels of palmitic (16:0) and palmitoleic (16:1n7) acids but lower levels of linoleic (18:2n6) acid and the polyunsaturated/saturated fatty acids ratio (P/S ratio). 
Among polyunsaturated fatty acids, levels of :
- dihomo-gamma-linolenic (20:3n6) and 
- arachidonic (20:4n6) acids were statistically significantly higher in incident hypertensives, compared with normotensives.

After adjustment for age, sex, body mass index, waist/hip ratio, smoking status, ethanol intake, education level, physical activity, and baseline systolic blood pressure in separate models, the odds ratio estimates of incident hypertension for an interquartile increment of a fatty acid in cholesterol esters were 1.26 (95% confidence interval (CI): 1.05, 1.51) for 16:0, 1.11 (95% CI: 0.96, 1.28) for 16:1n7, 1.01 (95% CI: 0.85, 1.21) for 20:3n6, 1.14 (95% CI: 1.03, 1.27) for 20:5n3, 0.81 (95% CI: 0.68, 0.96) for 18:2n6, and 0.83 (95% CI: 0.70, 0.99) for the P/S ratio. 
The authors conclude that reduced levels of linoleic acid and the P/S ratio and elevated levels of palmitic and arachidonic acids are associated with a higher risk of hypertension.

NOTA: l'acido alfa linolenico 18:3 n 3 (ALA) riduce la trasformazione dell'ac. Linoleico 18:2 n 6 in di-omo-gamma -linlenico e arachidonico.

Eur J Clin Nutr 2000 Dec;54(12):865-871 
Associations of alpha-linolenic acid and linoleic acid with risk factors for coronary heart disease.
Bemelmans WJ, Muskiet FA, Feskens EJ, de Vries JH, Broer J, May JF, Jong BM.
University of Groningen, Department of Family Medicine, Groningen, The Netherlands. w.bemelmans@med.rug.nl

BACKGROUND: Prevention of coronary heart disease (CHD) in high-risk subjects. 
OBJECTIVE: To investigate the associations of dietary intake of alpha-linolenic acid (ALA) and linoleic acid (LA) as assessed by food frequency questionnaire and in the plasma cholesteryl ester (CE), with CHD risk factors. 
DESIGN: Baseline data of a double-blind, randomized placebo-controlled trial. Subjects have hypercholesterolemia (6.0-8.0 mmol/l) and at least two other CHD risk factors (n=266). 
RESULTS: The reported dietary ALA and LA intakes and the LA/ALA ratio were associated with the contents in the CE (r=0.37, r=0.21, and r=0.42, respectively; P<0.01).
In multivariate analysis, CE ALA was inversely associated with diastolic blood pressure (r=-0.13; P<0.05) 
and positively with serum triacylglycerol (r=0.13; P<0.05), and CE LA was inversely associated with serum triacylglycerol (r=-0.32; P<0.01). The CE LA/ALA ratio was strongly inversely associated with CE ALA (r=-0.95; P<0.01). 
In the lowest quintile of CE ALA, mean dietary intake was 0.4 energy % ALA (1.2 g/day), 8.4 energy % LA and an LA/ALA ratio of 21, and in the highest quintile 0.6 energy % ALA (1.7 g/day), 6.8 energy % LA and 12 (ratio). In the lowest quintile of CE ALA the diastolic blood pressure was 4 mm Hg lower (P trend<0.05), and the serum triacylglycerol 0.3 mmol/l higher (P trend NS) when compared with the top quintile. 

CONCLUSIONS: In a CHD high-risk population with LA-rich background diet, these cross-sectional data suggest that replacing LA in the diet by ALA may decrease diastolic blood pressure, and may increase serum triacylglycerol concentration.

Vopr Pitan 1997;5:15-17 
[Effect of antiatherosclerotic diet, containing polyunsaturated fatty acids of the omega-3 family from flax oil, on fatty acid composition of cell membranes of patients with ischemic heart disease. Hypertensive disease and hyperlipoproteinemia].[Article in Russian]Rozanova IA, Pogozheva AV, Kupakova SN, Lupinovich VL, Karagodina ZV, Levachev MM, Samsonov MA.Use flax oil as a vegetative source of PUFA omega-3 in diet of patients with ischemic heart disease, hyperlipidemia and high blood pressure resulted in positive dynamic of clinical manifestation, blood lipids and coagulograms of the patient. Pronounced influence on membrane lipids of erythrocytes was revealed: significantly increased a quota an linolenic, eicosapentaenic and docosahexaenic PUFA against a background of reducing a level of linoleic acid.