Hypertension evening primrose

It is claimed that chronic deficiency of arachidonic acid can lead to a number of medical problems that can be overcome by supplementation of a normal diet with evening primrose oil. Supplementation is claimed to lead to an alleviation of eczema reduction in premenstrual tension and breast pain during menstruation improvement in some chronic inflammatory and autoimmune diseases reduction in blood pressure in hypertensive patients and reduction in blood cholesterol levels. As might be expected, these claims are controversial, but they serve to illustrate how basic biochemical information can lead to a considerable lay interest in a subject. 

Watanabe, Y., Manku, M.S., Jenkins, D.K., Mitchell, J., and Horrobin, D.E. (1988) The Effects of Short-Term Dietary Supplementation with Evening Primrose Oil on Fatty Acid and Prostaglandin Release from Perfused Mesenteric Vascular Beds in Spontaneously Hypertensive Rats, Awtr. Res. S, 517-528. 

Engler, MM. (1993) Comparative Study of Diets Enriched with Evening Primrose, Blackcurrant, Borage, or Fungal Oils on Blood Pressure and Pressor Responses in Spontaneously Hypertensive Rats, Prostag. Leukotr. Ess. 49,809-814. 

Animal and human studies have shown that PUFA significantly lower blood pressure. In hypertensive rats, blackcurrant seed oil effected a greater reduction of blood pressure than did borage oil or evening primrose oil in a 7-week study (Engler, 1993). Whether this was due to the stearidonic acid remains open. Blackcurrant oil decreased significantly the resting diastolic blood pressure in mildly hypertensive men when compared with safflower oil in a double-blind, parallel study (Defeme and Leeds, 1996). 

Engler, MM (1993) Comparative study of diets enriched with evening primrose, blackcurrant, borage or fungal oils on blood pressure and pressor responses in spontaneously hypertensive rats. Prostaglandins Leukotr. Essent. Fatty Acids, 49, 809-814. 

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